History of nuclear weapons
Encyclopedia
The history of nuclear weapons chronicles the development of nuclear weapons. Nuclear weapons possess enormous destructive potential derived from nuclear fission
or nuclear fusion
reactions. Starting with scientific breakthroughs of the 1930s
that made their development possible, and continuing through the nuclear arms race
and nuclear testing
of the Cold War
, the issues of proliferation
and possible use for terrorism still remain in the early 21st century.
The first fission weapons were developed jointly by the United States
, Britain
and Canada
during World War II
in what was called the Manhattan Project
to counter the assumed Nazi German atomic bomb project
. In August 1945 two were dropped on Japan
ending the Pacific War
. An international team was dispatched to help work on the project. The Soviet Union
started development shortly thereafter with their own atomic bomb project
, and not long after that both countries developed even more powerful fusion weapons called "hydrogen bombs."
During the Cold War
, the Soviet Union and United States each acquired nuclear weapons arsenals numbering in the thousands, placing many of them onto rocket
s that could hit targets anywhere in the world. Currently there are at least nine countries with functional nuclear weapons. A considerable amount of international negotiating has focused on the threat of nuclear warfare
and the proliferation
of nuclear weapons to new nations or groups.
There have been (at least) four major false alarms, the most recent in 1995, that resulted in the activation of either the US's or Russia's nuclear attack early warning protocols.
In the first decades of the twentieth century, physics
was revolutionised with developments in the understanding of the nature of atom
s. In 1898, French physicist Pierre Curie
had discovered that pitchblende
, an ore of uranium
, contained a substance—which they named radium
—that emitted large amounts of radioactivity. This raised hopes among scientists and laymen that the elements around us could contain tremendous amounts of unseen energy, waiting to be harnessed.
Experiments by Ernest Rutherford
in 1911 indicated that the vast majority of an atom's mass
was contained in a very small nucleus
at its core, made up of proton
s, surrounded by a web of electron
s. In 1932, James Chadwick
discovered that the nucleus contained another particle, the neutron
, and in the same year John Cockcroft
and Ernest Walton
"split the atom" for the first time, the first occasion on which an atomic nucleus of one element had been successfully changed to a different nucleus by artificial means.
In 1934 the idea of chain reaction via neutron was proposed by Leó Szilárd
, who patented the idea of the atomic bomb. The patent was assigned by him to the Admiralty
(the controlling organisation for Britain's Royal Navy
) in 1936, this 'sleight of hand' being necessary to prevent wider publication of the idea, as an Admiralty patent could be covered by the Official Secrets Act. In a very real sense, Szilárd was the father of the atomic bomb academically.
In 1934, French physicists Irène
and Frédéric Joliot-Curie
discovered that artificial radioactivity could be induced in stable elements by bombarding them with alpha particle
s, and in the same year Italian physicist Enrico Fermi
reported similar results when bombarding uranium with neutrons.
In December 1938, the German chemists Otto Hahn
and Fritz Strassmann
sent a manuscript to Naturwissenschaften
reporting they had detected the element barium
after bombarding uranium
with neutrons; Lise Meitner
and her nephew Otto Robert Frisch
correctly interpreted these results as being nuclear fission
. Frisch confirmed this experimentally on January 13, 1939.
Even before it was published, Meitner’s and Frisch’s interpretation of the work of Hahn and Strassmann crossed the Atlantic Ocean with Niels Bohr
, who was to lecture at Princeton University
. Isidor Isaac Rabi
and Willis Lamb
, two Columbia University
physicists working at Princeton, heard the news and carried it back to Columbia. Rabi said he told Fermi; Fermi gave credit to Lamb. Bohr soon thereafter went from Princeton to Columbia to see Fermi. Not finding Fermi in his office, Bohr went down to the cyclotron area and found Herbert Anderson. Bohr grabbed him by the shoulder and said: “Young man, let me explain to you about something new and exciting in physics.”
It was clear to a number of scientists at Columbia that they should try to detect the energy released in the nuclear fission of uranium from neutron bombardment. On January 25, 1939 an experimental team at Columbia University conducted the first nuclear fission experiment in the United States in the basement of Pupin Hall
. The team members were Herbert L. Anderson
, Eugene T. Booth
, John R. Dunning
, Enrico Fermi
, G. Norris Glasoe
, and Francis G. Slack
.
As Germany
occupied Czechoslovakia
in 1938 and then the German army marched into Poland
in 1939, beginning World War II
, many of Europe's top physicists had already begun to flee from the imminent conflict. Scientists on both sides of the conflict were well aware of the possibility of utilizing nuclear fission as a weapon, but at the time no one was quite sure how it could be done. In the early years of the war, physicists abruptly stopped publishing on the topic of fission, an act of self-censorship to keep the opposing side from gaining any advantage.
By the beginning of World War II, scientists of the Allied
nations were concerned that Germany might have its own project
to develop fission-based weapons. Organized research first began in Britain as part of the "Tube Alloys
" project, and in the United States a small amount of funding was given for research into uranium weapons, starting in 1939 with the Uranium Committee under Lyman James Briggs
.
At the urging of British scientists who had made crucial calculations indicating that a fission weapon could be completed within only a few years, by 1941 the project had been wrested into better bureaucratic hands, and in 1942 came under the auspices of a Military Policy Committee led by General Leslie Groves
. This was known as the Manhattan Project
.
Its scientific team led by the American physicist Robert Oppenheimer
, the project brought together the top scientific minds of the day, including many exiles from Europe, with the production power of American industry for the goal of producing fission-based explosive devices before Germany. Britain and the U.S. agreed to pool their resources and information for the project, but the other Allied power—the Soviet Union
—was not informed.
A massive industrial and scientific undertaking, the Manhattan Project involved many of the world's leading physicists in the scientific and development aspects. The U.S. made an unprecedented investment in the project, spread across more than 30 sites in the U.S. and Canada. They centralized scientific development at Los Alamos
, a secret laboratory that was previously a small ranch school near Santa Fe
, New Mexico
.
Uranium appears in nature primarily in two isotopes: uranium-238
and uranium-235
. When the nucleus of uranium-235 absorbs a neutron, it undergoes nuclear fission, splitting into two "fission products" and releasing energy and, on average, 2.5 neutrons. Uranium-238, on the other hand, absorbs neutrons but does not split, effectively putting a stop to any ongoing fission reaction.
Scientists discovered that an atomic bomb based on uranium would require at least 80% pure uranium-235, otherwise the presence of uranium-238 would quickly curtail the nuclear chain reaction
. The team of scientists working at the Manhattan Project quickly realized that one of the largest problems was how to remove uranium-235 from natural uranium, which was composed of 99.3% uranium-238.
They developed two methods during the wartime project, which both took advantage of the fact that uranium-238 has a slightly greater atomic mass than uranium-235: electromagnetic separation and gaseous diffusion
—methods that separated isotopes based on their differing weights. Another secret site was erected at rural Oak Ridge, Tennessee
, for the large-scale production and purification of the rare isotope, which required considerable investment. At the time, K-25
, one of the Oak Ridge facilities, was the world's largest factory under one roof. The Oak Ridge site employed tens of thousands of employees at its peak, most of whom had no idea what they were working on.
Although uranium-238 cannot be used for the initial stage of an atomic bomb, when U-238 absorbs a neutron, it transforms first into an unstable element, uranium-239, and then decays into neptunium
-239, and finally the relatively stable plutonium
-239, an element that does not exist in nature. Plutonium is also fissile
and can be used to create a fission reaction, and after Enrico Fermi
achieved the world's first sustained and controlled nuclear chain reaction in the creation of the first "atomic pile"—a primitive nuclear reactor
—in a basement at the University of Chicago
, massive reactors were secretly created at what is now known as Hanford Site
in Washington State – using water from the Columbia River
in the cooling process – to transform uranium-238 into plutonium for a bomb.
For a fission weapon to operate, there must be a critical mass—the amount needed for a self-sustaining nuclear chain reaction—of fissile material bombarded with neutrons at any one time. The simplest form of nuclear weapon is a gun-type fission weapon
, where a sub-critical mass of fissile material (such as uranium-235) would be shot at another sub-critical mass of fissile material. The result would be a super-critical mass that, when bombarded with neutrons, would undergo fission at a rapid rate and create the desired explosion. The weapons envisaged in 1942 were the two gun-type weapons, Little Boy
(uranium
) and Thin Man
(plutonium
), and the Fat Man
plutonium implosion bomb.
In early 1943 Oppenheimer determined that two projects should proceed forwards: the "Thin Man" project (plutonium gun) and the "Fat Man" project (plutonium implosion). The plutonium gun was to receive the bulk of the research effort, as it was the project with the most uncertainty involved. It was assumed that the uranium gun-type bomb could then be adapted from it.
But in April 1944 it was found by Emilio Segrè that the plutonium produced by the Hanford reactors had too high a level of background neutron radiation, and underwent spontaneous fission
to a very small extent, due to the presence of impurities of the Pu-240 isotope. If such plutonium were used in a "gun assembly," the chain reaction would start in the split seconds before the critical mass was assembled, blowing the weapon apart before it would have any great effect (this is known as a fizzle).
As a result, development of Fat Man
(the implosion bomb) was given high priority. Chemical explosives were used to implode a sub-critical sphere of plutonium, thus increasing its density and making it into a critical mass. The difficulties with implosion centered on the problem of making the chemical explosives deliver a perfectly uniform shock wave upon the plutonium sphere— if it were even slightly asymmetric, the weapon would fizzle (which would be expensive, messy, and not a very effective military device). This problem was circumvented by the use of hydrodynamic "lenses"—explosive materials of differing densities—which would focus the blast waves inside the imploding sphere, akin to the way in which an optical lens focuses light rays.
After D-Day
, General Groves ordered a team of scientists—Project Alsos
—to follow eastward-moving victorious Allied troops into Europe to assess the status of the German nuclear program (and to prevent the westward-moving Russians from gaining any materials or scientific manpower). They concluded that, while Germany had an atomic bomb program headed by Werner Heisenberg
, the government had not made a significant investment in the project, and it had been nowhere near success.
Historians claim to have found a rough schematic showing a Nazi nuclear bomb. Research was conducted in the German nuclear energy project
. In March 1945, a German scientific team was directed by the physicist Kurt Diebner
to develop a primitive nuclear device in Ohrdruf
, Thuringia
. Last ditch research was conducted in an experimental nuclear reactor at Haigerloch
.
At the time of the unconditional surrender of Germany on May 8, 1945, the Manhattan Project was still months away from producing a working weapon. That April, after the death of American President Franklin D. Roosevelt
, former Vice-President Harry S. Truman
was told about the secret wartime project for the first time.
Because of the difficulties in making a working plutonium bomb
, it was decided that there should be a test of the weapon, and Truman wanted to know for certain if it would work before his meeting with Stalin
at an upcoming conference
on the future of postwar Europe. On July 16, 1945, in the desert north of Alamogordo, New Mexico
, the first nuclear test took place, code-named "Trinity
," using a device nicknamed "the Gadget." The test, a plutonium implosion type device, released the equivalent of 19 kilotons of TNT
, far more powerful than any weapon ever used before. The news of the test's success was rushed to Truman, who used it as leverage at the Potsdam conference, held near Berlin
.
After hearing arguments from scientists and military officers over the possible uses of the weapons against Japan (though some recommended using them as "demonstrations" in unpopulated areas, most recommended using them against "built up" targets, a euphemistic
term for populated cities), Truman ordered the use of the weapons on Japanese cities, hoping it would send a strong message that would end in the capitulation of the Japanese leadership and avoid a lengthy invasion of the islands.
There were suggestions to drop the atomic bomb on Tokyo
, the capital of Japan, but concerns about Tokyo's cultural heritage forced a reconsideration of this plan. On May 10–11, 1945, the Target Committee at Los Alamos, led by Oppenheimer, recommended Kyoto, Hiroshima, Yokohama, and the arsenal at Kokura as possible targets. On August 6, 1945, a uranium-based weapon, "Little Boy
," was detonated above the Japanese city of Hiroshima
. Three days later, a plutonium-based weapon, "Fat Man
," was detonated above the city of Nagasaki. The atomic bombs killed at least one hundred thousand
Japanese outright, most of them civilians, with the heat, radiation, and blast effects.
Many tens of thousands would later die of radiation sickness and related cancers. Truman promised a "rain of ruin" if Japan did not surrender immediately, threatening to eliminate Japanese cities, one by one; Japan surrendered on August 15. Truman's threat was in fact a bluff
, since the US had but one remaining uranium-gun type bomb completed.
The Soviet Union
was not invited to share in the new weapons developed by the United States and the other Allies. During the war, information had been pouring in from a number of volunteer spies involved with the Manhattan Project (known in Soviet cables under the code-name of Enormoz), and the Soviet nuclear physicist Igor Kurchatov
was carefully watching the Allied weapons development. It came as no surprise to Stalin when Truman had informed him at the Potsdam conference that he had a "powerful new weapon." Truman was shocked at Stalin's lack of interest.
The Soviet spies in the U.S. project were all volunteers and none were Russians. One of the most valuable, Klaus Fuchs
, was a German émigré theoretical physicist who had been a part in the early British nuclear efforts and had been part of the UK mission to Los Alamos during the war. Fuchs had been intimately involved in the development of the implosion weapon, and passed on detailed cross-sections of the "Trinity" device to his Soviet contacts. Other Los Alamos spies—none of whom knew each other—included Theodore Hall
and David Greenglass
. The information was kept but not acted upon, as Russia was still too busy fighting the war in Europe to devote resources to this new project.
In the years immediately after World War II, the issue of who should control atomic weapons became a major international point of contention. Many of the Los Alamos scientists who had built the bomb began to call for "international control of atomic energy," often calling for either control by transnational organizations or the purposeful distribution of weapons information to all superpowers, but due to a deep distrust of the intentions of the Soviet Union, both in postwar Europe and in general, the policy-makers of the United States worked to attempt to secure an American nuclear monopoly.
A half-hearted plan for international control was proposed at the newly formed United Nations
by Bernard Baruch
("The Baruch Plan
"), but it was clear both to American commentators—and to the Soviets—that it was an attempt primarily to stymie Russian nuclear efforts. The Soviets vetoed the plan, effectively ending any immediate postwar negotiations on atomic energy, and made overtures towards banning the use of atomic weapons in general.
All the while, the Soviets had put their full industrial and manpower might into the development of their own atomic weapons. The initial problem for the Soviets was primarily one of resources—they had not scouted out uranium resources in the Soviet Union and the U.S. had made deals to monopolise the largest known (and high purity) reserves in the Belgian Congo
. The USSR used penal labour
to mine the old deposits in Czechoslovakia
—now an area under their control—and searched for other domestic deposits (which were eventually found).
Two days after the bombing of Nagasaki, the U.S. government released an official technical history of the Manhattan Project, authored by Princeton physicist Henry DeWolf Smyth
, known colloquially as the Smyth Report
. The sanitized summary of the wartime effort focused primarily on the production facilities and scale of investment, written in part to justify the wartime expenditure to the American public.
The Soviet program, under the suspicious watch of former NKVD
chief Lavrenty Beria (a participant and victor in Stalin's Great Purge
of the 1930s), would use the Report as a blueprint, seeking to duplicate as much as possible the American effort. The "secret cities" used for the Soviet equivalents of Hanford and Oak Ridge literally vanished from the maps for decades to come.
At the Soviet equivalent of Los Alamos, Arzamas-16
, physicist Yuli Khariton led the scientific effort to develop the weapon. Beria distrusted his scientists, however, and he distrusted the carefully collected espionage information. As such, Beria assigned multiple teams of scientists to the same task without informing each team of the other's existence. If they arrived at different conclusions, Beria would bring them together for the first time and have them debate with their newfound counterparts. Beria used the espionage information as a way to double-check the progress of his scientists, and in his effort for duplication of the American project even rejected more efficient bomb designs in favor of ones that more closely mimicked the tried-and-true "Fat Man
" bomb used by the U.S. against Nagasaki.
Working under a stubborn and scientifically ignorant administrator, the Soviet scientists struggled on. On August 29, 1949, the effort brought its results, when the USSR tested its first fission bomb, dubbed "Joe-1" by the U.S., years ahead of American predictions. The news of the first Soviet bomb was announced to the world first by the United States, which had detected the nuclear fallout
it generated from its test site in Kazakhstan
.
The loss of the American monopoly on nuclear weapons marked the first tit-for-tat of the nuclear arms race
. The response in the U.S. was one of apprehension, fear, and scapegoating, which would lead eventually into the Red-baiting tactics of McCarthyism
. Yet recent information from unclassified Venona intercepts and the opening of the KGB archives after the fall of the Soviet Union show that the USSR had useful spies that helped their program, although none were identified by McCarthy. Before this, though, President Truman announced a decision to begin a crash program that would develop a far more powerful weapon than those the U.S. used against Japan: the hydrogen bomb.
can be dated back to 1942. At the first major theoretical conference on the development of an atomic bomb hosted by J. Robert Oppenheimer at the University of California, Berkeley
, participant Edward Teller
directed the majority of the discussion towards Enrico Fermi
's idea of a "Super" bomb that would use the same reactions that powered the Sun
itself.
It was thought at the time that a fission weapon would be quite simple to develop and that perhaps work on a hydrogen bomb would be possible to complete before the end of the Second World War. However, in reality the problem of a "regular" atomic bomb was large enough to preoccupy the scientists for the next few years, much less the more speculative "Super." Only Teller continued working on the project—against the will of project leaders Oppenheimer and Hans Bethe
.
After the atomic bombings of Japan, many scientists at Los Alamos
rebelled against the notion of creating a weapon thousands of times more powerful than the first atomic bombs. For the scientists the question was in part technical—the weapon design was still quite uncertain and unworkable—and in part moral: such a weapon, they argued, could only be used against large civilian populations, and could thus only be used as a weapon of genocide.
Many scientists, such as Bethe, urged that the United States should not develop such weapons and set an example towards the Soviet Union. Promoters of the weapon, including Teller, Ernest Lawrence
, and Luis Alvarez
, argued that such a development was inevitable, and to deny such protection to the people of the United States—especially when the Soviet Union was likely to create such a weapon themselves—was itself an immoral and unwise act.
Oppenheimer, who was now head of the General Advisory Committee of the successor to the Manhattan Project, the Atomic Energy Commission
, presided over a recommendation against the development of the weapon. The reasons were in part because the success of the technology seemed limited at the time (and not worth the investment of resources to confirm whether this was so), and because Oppenheimer believed that the atomic forces of the United States would be more effective if they consisted of many large fission weapons (of which multiple bombs could be dropped on the same targets) rather than the large and unwieldy predictions of massive super bombs, for which there were a relatively limited amounts of targets of the size to warrant such a development.
Furthermore, were such weapons developed by both the U.S. and the USSR, they would be more effectively used against the U.S. than by it, as the U.S. had far more regions of dense industrial and civilian activity as targets for large weapons than the Soviet Union.
In the end, President Truman made the final decision, looking for a proper response to the first Soviet atomic bomb test in 1949. On January 31, 1950, Truman announced a crash program to develop the hydrogen (fusion) bomb. At this point, however, the exact mechanism was still not known: the "classical" hydrogen bomb, whereby the heat of the fission bomb would be used to ignite the fusion material, seemed highly unworkable. However, an insight by Los Alamos mathematician Stanislaw Ulam showed that the fission bomb and the fusion fuel could be in separate parts of the bomb, and that radiation of the fission bomb could first work in a way to compress the fusion material before igniting it.
Teller pushed the notion further, and used the results of the boosted-fission "George
" test (a boosted-fission device using a small amount of fusion fuel to boost the yield of a fission bomb) to confirm the fusion of heavy hydrogen elements before preparing for their first true multi-stage, Teller-Ulam hydrogen bomb
test. Many scientists initially against the weapon, such as Oppenheimer and Bethe, changed their previous opinions, seeing the development as being unstoppable.
The first fusion bomb was tested by the United States in Operation Ivy
on November 1, 1952, on Elugelab Island in the Enewetak (or Eniwetok) Atoll of the Marshall Islands
, code-named "Mike
." "Mike" used liquid deuterium
as its fusion fuel and a large fission weapon as its trigger. The device was a prototype design and not a deliverable weapon: standing over 20 ft (6 m) high and weighing at least 140,000 lb (64 t) (its refrigeration equipment added an additional 24000 lb (10,886.2 kg) as well), it could not have been dropped from even the largest planes.
Its explosion yielded 10.4 megatons
of energy—over 450 times the power of the bomb dropped onto Nagasaki— and obliterated Elugelab
, leaving an underwater crater 6240 ft (1.9 km) wide and 164 ft (50 m) deep where the island had once been. Truman had initially tried to create a media blackout about the test—hoping it would not become an issue in the upcoming presidential election—but on January 7, 1953, Truman announced the development of the hydrogen bomb to the world as hints and speculations of it were already beginning to emerge in the press.
Not to be outdone, the Soviet Union exploded its first thermonuclear device, designed by the physicist Andrei Sakharov
, on August 12, 1953, labeled "Joe-4" by the West. This created concern within the U.S. government and military, because, unlike "Mike," the Soviet device was a deliverable weapon, which the U.S. did not yet have. This first device though was arguably not a "true" hydrogen bomb, and could only reach explosive yields in the hundreds of kilotons (never reaching the megaton range of a "staged" weapon). Still, it was a powerful propaganda tool for the Soviet Union, and the technical differences were fairly oblique to the American public and politicians.
Following the "Mike" blast by less than a year, "Joe-4" seemed to validate claims that the bombs were inevitable and vindicate those who had supported the development of the fusion program. Coming during the height of McCarthyism
, the effect was most pronounced by the security hearings in early 1954, which revoked former Los Alamos director Robert Oppenheimer's security clearance on the grounds that he was unreliable, had not supported the American hydrogen bomb program, and had made long-standing left-wing ties in the 1930s. Edward Teller participated in the hearing as the only major scientist to testify against Oppenheimer, resulting in his virtual expulsion from the physics community.
On February 28, 1954, the U.S. detonated its first deliverable thermonuclear weapon (which used isotopes of lithium
as its fusion fuel), known as the "Shrimp" device of the "Castle Bravo
" test, at Bikini Atoll
, Marshall Islands
. The device yielded 15 megatons of energy, three times its expected yield, and became the worst radiological disaster in U.S. history. The combination of the unexpectedly large blast and poor weather conditions caused a cloud of radioactive nuclear fallout
to contaminate over 7000 square miles (18,129.9 km²), including Marshall Island natives and the crew of a Japanese fishing boat, as a snow-like mist. The contaminated islands were evacuated (and are still uninhabitable), but the natives received enough of a radioactive dose that they suffered far elevated levels of cancer
and birth defects in the years to come.
The crew of the Japanese fishing boat, Lucky Dragon 5, returned to port suffering from radiation sickness
and skin burns. Their cargo, many tons of contaminated fish, managed to enter into the market before the cause of their illness was determined. When a crew member died from the sickness and the full results of the contamination were made public by the U.S., Japanese concerns were reignited about the hazards of radiation and resulted in a boycott on eating fish (a main staple of the island country) for some weeks.
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The hydrogen bomb age had a profound effect on the thoughts of nuclear war
in the popular and military mind. With only fission bombs, nuclear war was something that possibly could be "limited." Dropped by planes and only able to destroy the most built up areas of major cities, it was possible for many to look at fission bombs as a technological extension of large-scale conventional bombing—such as the extensive firebombing
against Japan and Germany during World War II). Proponents brushed aside as grave exaggeration claims that such weapons could lead to worldwide death or harm.
Even in the decades before fission weapons, there had been speculation about the possibility for human beings to end all life on the planet, either by accident or purposeful maliciousness—but technology had not provided the capacity for such action. The great power of hydrogen bombs made world-wide annihilation possible.
The "Castle Bravo" incident itself raised a number of questions about the survivability of a nuclear war. Government scientists in both the U.S. and the USSR had insisted that fusion weapons, unlike fission weapons, were "cleaner," as fusion reactions did not produce the dangerously radioactive by-products of fission reactions. While technically true, this hid a more gruesome point: the last stage of a multi-staged hydrogen bomb often used the neutrons produced by the fusion reactions to induce fissioning in a jacket of natural uranium, and provided around half of the yield of the device itself.
This fission stage made fusion weapons considerably more "dirty" than they were made out to be. This was evident in the towering cloud of deadly fallout that followed the Bravo test. When the Soviet Union tested its first megaton device in 1955, the possibility of a limited nuclear war seemed even more remote in the public and political mind. Even cities and countries that were not direct targets would suffer fallout contamination. Extremely harmful fission products would disperse via normal weather patterns and embed in soil and water around the planet.
Speculation began to run towards what fallout and dust from a full-scale nuclear exchange would do to the world as a whole, rather than just cities and countries directly involved. In this way, the fate of the world was now tied to the fate of the bomb-wielding superpowers.
Throughout the 1950s
and the early 1960s
a number of trends were enacted between the U.S. and the USSR as they both endeavored in a tit-for-tat approach to disallow the other power from acquiring nuclear supremacy. This took form in a number of ways, both technologically and politically, and had massive political and cultural effects during the Cold War
.
The first atomic bombs dropped on Hiroshima and Nagasaki were large, custom-made devices, requiring highly trained personnel for their arming and deployment. They could be dropped only from the largest bomber planes—at the time the B-29 Superfortress
—and each plane could only hold a single bomb in its hold.
The first hydrogen bombs were similarly massive and complicated. This ratio of one plane to one bomb was still fairly impressive in comparison with conventional, non-nuclear weapons, but against other nuclear-armed countries it was considered a grave danger. In the immediate postwar years, the U.S. expended much effort on making the bombs "G.I.-proof"—capable of being used and deployed by members of the U.S. Army, rather than Nobel Prize–winning scientists. In the 1950s, the U.S. undertook a nuclear testing
program to improve the nuclear arsenal.
Starting in 1951, the Nevada Test Site
(in the Nevada
desert) became the primary location for all U.S. nuclear testing (in the USSR, Semipalatinsk Test Site
in Kazakhstan
served a similar role). Tests were divided into two primary categories: "weapons related" (verifying that a new weapon worked or looking at exactly how it worked) and "weapons effects" (looking at how weapons behaved under various conditions or how structures behaved when subjected to weapons).
In the beginning, almost all nuclear tests were either "atmospheric" (conducted above ground, in the atmosphere
) or "underwater" (such as some of the tests done in the Marshall Islands
). Testing was used as a sign of both national and technological strength, but also raised questions about the safety of the tests, which released nuclear fallout
into the atmosphere (most dramatically with the Castle Bravo
test in 1954, but in more limited amounts with almost all atmospheric nuclear testing).
Because testing was seen as a sign of technological development (the ability to design usable weapons without some form of testing was considered dubious), halts on testing were often called for as stand-ins for halts in the nuclear arms race
itself, and many prominent scientists and statesmen lobbied for a ban on nuclear testing. In 1958, the U.S., USSR, and the United Kingdom
(a new nuclear power) declared a temporary testing moratorium for both political and health reasons, but by 1961 the Soviet Union had broken the moratorium and both the USSR and the U.S. began testing with great frequency.
As a show of political strength, the Soviet Union tested the largest-ever nuclear weapon in October 1961, the massive Tsar Bomba
, which was tested in a reduced state with a yield of around 50 megatons
—in its full state it was estimated to have been around 100 Mt. The weapon was largely impractical for actual military use, but was hot enough to induce third-degree burns at a distance of 62 mi (100 km) away. In its full, "dirty" design, it would have increased the amount of worldwide fallout since 1945 by 25%.
In 1963, all nuclear and many non-nuclear states signed the Limited Test Ban Treaty, pledging to refrain from testing nuclear weapons in the atmosphere, underwater, or in outer space. The treaty permitted underground tests.
Most tests were considerably more modest, and worked for direct technical purposes as well as their potential political overtones. Weapons improvements took on two primary forms. One was an increase in efficiency and power, and within only a few years fission bombs were developed that were many times more powerful than the ones created during World War II. The other was a program of miniaturization, reducing the size of the nuclear weapons.
Smaller bombs meant that bombers could carry more of them, and also that they could be carried on the new generation of rocket
s in development in the 1950s and 1960s. U.S. rocket science received a large boost in the postwar years, largely with the help of engineers acquired from the Nazi rocketry program. These included scientists such as Wernher von Braun
, who had helped design the V-2 rocket
s the Nazis launched across the English Channel
. An American program, Project Paperclip, had endeavored to move German scientists into American hands (and away from Soviet hands) and put them to work for the U.S.
, first deployed by the U.S. in 1953—were surface-to-surface missiles with relatively short ranges (around 15 mi/25 km maximum) and yields around twice the size of the first fission weapons. The limited range meant they could only be used in certain types of military situations. U.S. rockets could not, for example, threaten Moscow
with an immediate strike, and could only be used as "tactical" weapons (that is, for small-scale military situations).
"Strategic" weapons—weapons that could threaten an entire country—relied, for the time being, on long-range bombers that could penetrate deep into enemy territory. In the U.S., this requirement led, in 1946, to creation of the Strategic Air Command
—a system of bomber
s headed by General Curtis LeMay
(who previously presided over the firebombing of Japan
during WWII). In operations like Chrome Dome
, SAC kept nuclear-armed planes in the air 24 hours a day, ready for an order to attack Moscow.
These technological possibilities enabled nuclear strategy
to develop a logic considerably different than previous military thinking allowed. Because the threat of nuclear warfare
was so awful, it was first thought that it might make any war of the future impossible. President Dwight D. Eisenhower
's doctrine of "massive retaliation" in the early years of the Cold War was a message to the USSR, saying that if the Red Army
attempted to invade the parts of Europe not given to the Eastern bloc
during the Potsdam Conference (such as West Germany
), nuclear weapons would be used against the Soviet troops and potentially the Soviet leaders.
With the development of more rapid-response technologies (such as rockets and long-range bombers), this policy began to shift. If the Soviet Union also had nuclear weapons and a policy of "massive retaliation" was carried out, it was reasoned, then any Soviet forces not killed in the initial attack, or launched while the attack was ongoing, would be able to serve their own form of nuclear "retaliation" against the U.S. Recognizing that this was an undesirable outcome, military officers and game theorists
at the RAND
think tank
developed a nuclear warfare strategy that was eventually called Mutually Assured Destruction (MAD).
MAD divided potential nuclear war into two stages: first strike
and second strike
. First strike meant the first use of nuclear weapons by one nuclear-equipped nation against another nuclear-equipped nation. If the attacking nation did not prevent the attacked nation from a nuclear response, the attacked nation would respond with a second strike against the attacking nation. In this situation, whether the U.S. first attacked the USSR or the USSR first attacked the U.S., the end result would be that both nations would be damaged to the point of utter social collapse.
According to game theory, because starting a nuclear war was suicidal, no logical country would "shoot first." However, if a country could launch a first strike that utterly destroyed the target country's ability to respond, that might give that country the confidence to initiate a nuclear war. The object of a country operating by the MAD doctrine is to deny the opposing country this first strike capability.
MAD played on two seemingly opposed modes of thought: cold logic and emotional fear. The English phrase MAD was often known by , "nuclear deterrence," was translated by the French as "dissuasion," and "terrorization" by the Russians. This apparent paradox of nuclear war was summed up by British Prime Minister Winston Churchill
as "the worse things get, the better they are"—the greater the threat of mutual destruction, the safer the world would be.
This philosophy made a number of technological and political demands on participating nations. For one thing, it said that it should always be assumed that an enemy nation may be trying to acquire first strike capability, which must always be avoided. In American politics this translated into demands to avoid "bomber gap
s" and "missile gap
s" where the Soviet Union could potentially "out shoot" the Americans. It also encouraged the production of thousands of nuclear weapons by both the U.S. and the USSR, far more than needed to simply destroy the major civilian and military infrastructures of the opposing country.
These policies and strategies were satirized in the 1964 Stanley Kubrick
film Dr. Strangelove, in which the Soviets, unable to keep up with the US's first strike capability, instead plan for MAD by building a Doomsday Machine
, and thus, after a (literally) mad US General orders a nuclear attack on the USSR, the end of the world is brought about.
The policy also encouraged the development of the first early warning systems. Conventional war, even at its fastest, was fought over days and weeks. With long-range bombers, from the start of an attack to its conclusion was mere hours. Rockets could reduce a conflict to minutes. Planners reasoned that conventional command and control
systems could not adequately react to a nuclear attack, so great lengths were taken to develop computer
s that could look for enemy attacks and direct rapid responses.
The U.S., poured massive funding into development of SAGE
, a system that could track and intercept enemy bomber aircraft using information from remote radar
stations. It was the first computer system to feature real-time
processing, multiplexing
, and display device
s. It was the first "general" computing machine, and a direct predecessor of modern computers.
, both the United States and the Soviet Union had developed intercontinental ballistic missile
s, which could be launched from extremely remote areas far away from their target. They had also developed submarine-launched ballistic missile
s, which had less range but could be launched from submarines very close to the target without any radar warning. This made any national protection from nuclear missiles increasingly impractical.
The military realities made for a precarious diplomatic situation. The international politics of brinkmanship
led leaders to exclaim their willingness to participate in a nuclear war rather than concede any advantage to their opponents, feeding public fears that their generation may be the last. Civil defense
programs undertaken by both superpowers, exemplified by the construction of fallout shelters and urging civilians about the "survivability" of nuclear war, did little to ease public concerns.
The climax of brinksmanship came in early 1962, when an American U-2
spy plane photographed a series of launch sites for medium-range ballistic missiles being constructed on the island of Cuba
, just off the coast of the southern United States, beginning what became known as the Cuban Missile Crisis
. The U.S. administration of John F. Kennedy
concluded that the Soviet Union, then led by Nikita Khrushchev
, was planning to station Russian nuclear missiles on the island, which was under the control of Communist Fidel Castro
. On October 22, Kennedy announced the discoveries in a televised address. He announced a naval blockade
around Cuba that would turn back Soviet nuclear shipments, and warned that the military was prepared "for any eventualities." The missiles had 2,400 mile (4,000 km) range, and would allow the Soviet Union to quickly destroy many major American cities on the Eastern Seaboard
if a nuclear war began.
The leaders of the two superpowers stood nose to nose, seemingly poised over the beginnings of a third world war
. Khrushchev's ambitions for putting the weapons on the island were motivated in part by the fact that the U.S. had stationed similar weapons in Britain
, Italy
, and nearby Turkey
, and had previously attempted to sponsor an invasion of Cuba the year before in the failed Bay of Pigs Invasion
. On October 26, Khrushchev sent a message to Kennedy offering to withdraw all missiles if Kennedy committed to a policy of no future invasions of Cuba. Khrushchev worded the threat of assured destruction eloquently:
A day later, however, the Russians sent another message, this time demanding that the U.S. remove its missiles from Turkey before any missiles were withdrawn from Cuba. On the same day, a U-2 plane was shot down over Cuba and another almost intercepted over Russia, as Soviet merchant ships neared the quarantine zone. Kennedy responded by accepting the first deal publicly, and sending his brother Robert to the Soviet embassy to accept the second deal privately.
On October 28, the Soviet ships stopped at the quarantine line and, after some hesitation, turned back towards the Soviet Union. Khrushchev announced that he had ordered the removal of all missiles in Cuba, and U.S. Secretary of State Dean Rusk
was moved to comment, "We went eyeball to eyeball, and the other fellow just blinked."
The Crisis was later seen as the closest the U.S. and the USSR ever came to nuclear war and had been narrowly averted by last-minute compromise by both superpowers. Fears of communication difficulties led to the installment of the first hotline
, a direct link between the superpowers that allowed them to more easily discuss future military activities and political maneuverings. It had been made clear that missiles, bombers, submarines, and computerized firing systems made escalating any situation to Armageddon far more easy than anybody desired.
After stepping so close to the brink, both the U.S. and the USSR worked to reduce their nuclear tensions in the years immediately following. The most immediate culmination of this work was the signing of the Partial Test Ban Treaty
in 1963, in which the U.S. and USSR agreed to no longer test nuclear weapons in the atmosphere, underwater, or in outer space. Testing underground continued, allowing for further weapons development, but the worldwide fallout risks were purposefully reduced, and the era of using massive nuclear tests as a form of saber-rattling ended.
In December 1979, NATO decided to deploy cruise and Pershing II missiles in Western Europe in response to Soviet deployment of intermediate range mobile missiles, and in the early 1980s, a "dangerous Soviet-US nuclear confrontation" arose. In New York on June 12, 1982, one million people gathered to protest nuclear weapons, and to support the second UN Special Session on Disarmament. As the nuclear abolitionist movement grew, there were many protests at the Nevada Test Site
. For example, on February 6, 1987, nearly 2,000 demonstrators, including six members of Congress, protested against nuclear weapons testing and more than 400 people were arrested. Four of the significant groups organizing this renewal of anti-nuclear activism
were Greenpeace
, The American Peace Test, The Western Shoshone, and Nevada Desert Experience
.
The United Kingdom had been an integral part of the Manhattan Project
following the Quebec Agreement
in 1943. The passing of the McMahon Act by the United States in 1946 unilaterally broke this partnership and prevented the passage of any further information to the United Kingdom. The British Government, under Clement Attlee
, determined that a British Bomb was essential. Because of British involvement in the Manhattan Project, Britain had extensive knowledge in some areas, but not in others.
An improved version of 'Fat Man' was developed, and on 26 February 1952, Prime Minister Winston Churchill
announced that the United Kingdom also had an atomic bomb and a successful test
took place on the 3rd October 1952. At first these were free-fall bombs, intended for use by the V Force
of jet bombers. A Vickers Valiant
dropped the first UK nuclear weapon on 11 October 1956 at Maralinga, South Australia
. Later came a missile, Blue Steel
, intended for carriage by the V Force bombers, and then the Blue Streak
medium-range ballistic missile
(later canceled). Anglo-American cooperation on Nuclear weapons was restored by the 1958 US-UK Mutual Defence Agreement
. As a result of this and the Polaris Sales Agreement
, the United Kingdom has bought United States designs for submarine missiles and fitted its own warheads. It retains full independent control over the use of the missiles. It no longer possesses any free-fall bombs.
France had been heavily involved in nuclear research before World War II
through the work of the Joliot-Curie
s. This was discontinued after the war because of the instability of the Fourth Republic
and lack of finances. However, in the 1950s, France launched a civil nuclear research program, which produced plutonium as a byproduct.
In 1956, France formed a secret Committee for the Military Applications of Atomic Energy and a development program for delivery vehicles. With the return of Charles de Gaulle
to the French presidency in 1958, final decisions to build a bomb were made, which led to a successful test in 1960. Since then, France has developed and maintained its own nuclear deterrent
.
In 1951, China and the Soviet Union signed an agreement whereby China supplied uranium ore in exchange for technical assistance in producing nuclear weapons. In 1953, China established a research program under the guise of civilian nuclear energy. Throughout the 1950s the Soviet Union provided large amounts of equipment. But as the relations between the two countries worsened the Soviets reduced the amount of assistance and, in 1959, refused to donate a bomb for copying purposes. Despite this, the Chinese made rapid progress and tested an atomic bomb on the October 16, 1964 at Lop Nur
. They tested a nuclear missile on October 25, 1966, and a hydrogen bomb on June 14, 1967.
Chinese nuclear warheads were produced from 1968 and thermonuclear warheads from 1974. It is also thought that Chinese warheads have been successfully miniaturised from 2200 kg to 700 kg through the use of designs obtained by espionage
from the United States. The current number of weapons is unknown owing to strict secrecy, but it is thought that up to 2000 warheads may have been produced, though far fewer may be available for use. China is the only nuclear weapons state to have guaranteed the non-first use of nuclear weapons.
After World War II, the balance of power
between the Eastern and Western blocs and the fear of global destruction prevented the further military use of atomic bombs. This fear was even a central part of Cold War
strategy, referred to as the doctrine of Mutually Assured Destruction ("MAD" for short). So important was this balance to international political stability that a treaty, the Anti-Ballistic Missile Treaty
(or ABM treaty), was signed by the U.S. and the USSR
in 1972 to curtail the development of defenses against nuclear weapons and the ballistic missile
s that carry them. This doctrine resulted in a large increase in the number of nuclear weapons, as each side sought to ensure it possessed the firepower to destroy the opposition in all possible scenarios and against all perceived threats.
Early delivery systems for nuclear devices were primarily bombers like the United States B-29 Superfortress
and Convair B-36
, and later the B-52 Stratofortress
. Ballistic missile systems, based on Wernher von Braun
's World War II designs (specifically the V2 rocket), were developed by both United States and Soviet Union teams (in the case of the U.S., effort was directed by the German scientists and engineers although the Soviet Union also made extensive use of captured German scientists, engineers, and technical data).
These systems were used to launch satellites, such as Sputnik, and to propel the Space Race
, but they were primarily developed to create Intercontinental Ballistic Missiles (ICBMs) that could deliver nuclear weapons anywhere on the globe. Development of these systems continued throughout the Cold War
—though plans and treaties, beginning with the Strategic Arms Limitation Treaty (SALT I), restricted deployment of these systems until, after the fall of the Soviet Union, system development essentially halted, and many weapons were disabled and destroyed (see nuclear disarmament
).
There have been a number of potential nuclear disasters. Following air accidents U.S. nuclear weapons have been lost near Atlantic City, New Jersey
(1957); Savannah, Georgia
(1958) (see Tybee Bomb
); Goldsboro, North Carolina
(1961); off the coast of Okinawa (1965); in the sea near Palomares
, Spain
(1966) (see 1966 Palomares B-52 crash); and near Thule, Greenland (1968) (see 1968 Thule Air Base B-52 crash). Most of the lost weapons were recovered, the Spanish device after three months' effort by the DSV Alvin
and DSV Aluminaut
.
The Soviet Union was less forthcoming about such incidents, but the environmental group Greenpeace
believes that there are around forty non-U.S. nuclear devices that have been lost and not recovered, compared to eleven lost by America, mostly in submarine disasters. The U.S. has tried to recover Soviet devices, notably in the 1974 Operation Jennifer using the specialist salvage vessel Hughes Glomar Explorer.
On January 27, 1967, more than 60 nations signed the Outer Space Treaty
, banning nuclear weapons in space.
The end of the Cold War
failed to end the threat of nuclear weapon use, although global fears of nuclear war
reduced substantially.
In a major move of symbolic de-escalation, Boris Yeltsin
, on January 26, 1992, announced that Russia
planned to stop targeting United States
cities with nuclear weapons.
, the second nuclear age—proliferation of nuclear weapons
among lesser powers and for reasons other than the American-Soviet rivalry—really began with the end of the Cold War.
After the collapse of Eastern Military High Command
and the disintegration
of Pakistan as a result of 1971 Winter war
, Bhutto
of Pakistan launched and embarked the scientific research on nuclear weapons. This programme was delegated to Munir Ahmad Khan
, Abdul Qadeer Khan
, and Salam
who later go on to win the Nobel Prize
. India's first atomic-test explosion was in 1974 with Smiling Buddha
, which it described as a "peaceful nuclear explosion". The Indian test caused Pakistan to spurred its programme, and with Dr. A. Q. Khan, the ISI conduct successful espionage operations in the Netherlands, while also developing the programme ingeniously on the other side. India
tested fission and perhaps fusion devices in 1998 (See Shakti), and Pakistan successfully tested fission devices that same year (See Chagai-I
), raising concerns that they would use nuclear weapons on each other. All of the former Soviet bloc countries with nuclear weapons (Belarus
, Ukraine
, and Kazakhstan
) returned their warheads to Russia
by 1996.
In January 2004, metallurgist and top weapon scientist Abdul Qadeer Khan confessed to having been a part of an international proliferation
network of materials, knowledge, and machines from Pakistan to Libya
, Iran
, and North Korea
.
South Africa
also had an active program to develop uranium-based nuclear weapons, but dismantled its nuclear weapon program in the 1990s
. Experts do not believe it actually tested such a weapon, though it later claimed it constructed several crude devices that it eventually dismantled. In the late 1970s
American spy satellites detected a "brief, intense, double flash of light near the southern tip of Africa." Known as the Vela Incident
, it was speculated to have been a South African or possibly Israeli nuclear weapons test, though some feel that it may have been caused by natural events or a detector malfunction.
Israel
is widely believed to possess an arsenal of potentially up to several hundred nuclear warheads, but this has never been officially confirmed or denied (though the existence of their Dimona nuclear facility
was confirmed by Mordechai Vanunu
in 1986).
North Korea announced in 2003 that it also had several nuclear explosives though it has not been confirmed and the validity of this has been a subject of scrutiny amongst weapons experts. The first detonation of a nuclear weapon
by the Democratic People's Republic of Korea was the 2006 North Korean nuclear test
, conducted on October 9, 2006. On May 25, 2009 North Korea continued nuclear testing, violating United Nations Security Council Resolution 1718
.
In Iran
, Ayatollah
Ali Khamenei
issued a fatwa
forbidding the production, stockpiling and use of nuclear weapons on August 9, 2005. The full text of the fatwa was released in an official statement at the meeting of the International Atomic Energy Agency (IAEA) in Vienna. Despite this, however, there is mounting concern in many nations about Iran's refusal to halt its nuclear power program, which many (including some members of the US government) fear is a cover for weapons development. (See Iran and weapons of mass destruction
.)
Nuclear fission
In nuclear physics and nuclear chemistry, nuclear fission is a nuclear reaction in which the nucleus of an atom splits into smaller parts , often producing free neutrons and photons , and releasing a tremendous amount of energy...
or nuclear fusion
Nuclear fusion
Nuclear fusion is the process by which two or more atomic nuclei join together, or "fuse", to form a single heavier nucleus. This is usually accompanied by the release or absorption of large quantities of energy...
reactions. Starting with scientific breakthroughs of the 1930s
1930s
File:1930s decade montage.png|From left, clockwise: Dorothea Lange's photo of the homeless Florence Thompson show the effects of the Great Depression; Due to the economic collapse, the farms become dry and the Dust Bowl spreads through America; The Battle of Wuhan during the Second Sino-Japanese...
that made their development possible, and continuing through the nuclear arms race
Nuclear arms race
The nuclear arms race was a competition for supremacy in nuclear warfare between the United States, the Soviet Union, and their respective allies during the Cold War...
and nuclear testing
Nuclear testing
Nuclear weapons tests are experiments carried out to determine the effectiveness, yield and explosive capability of nuclear weapons. Throughout the twentieth century, most nations that have developed nuclear weapons have tested them...
of the Cold War
Cold War
The Cold War was the continuing state from roughly 1946 to 1991 of political conflict, military tension, proxy wars, and economic competition between the Communist World—primarily the Soviet Union and its satellite states and allies—and the powers of the Western world, primarily the United States...
, the issues of proliferation
Nuclear proliferation
Nuclear proliferation is a term now used to describe the spread of nuclear weapons, fissile material, and weapons-applicable nuclear technology and information, to nations which are not recognized as "Nuclear Weapon States" by the Treaty on the Nonproliferation of Nuclear Weapons, also known as the...
and possible use for terrorism still remain in the early 21st century.
The first fission weapons were developed jointly by the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, Britain
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
and Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
during World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
in what was called the Manhattan Project
Manhattan Project
The Manhattan Project was a research and development program, led by the United States with participation from the United Kingdom and Canada, that produced the first atomic bomb during World War II. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the US Army...
to counter the assumed Nazi German atomic bomb project
German nuclear energy project
The German nuclear energy project, , was an attempted clandestine scientific effort led by Germany to develop and produce the atomic weapons during the events involving the World War II...
. In August 1945 two were dropped on Japan
Atomic bombings of Hiroshima and Nagasaki
During the final stages of World War II in 1945, the United States conducted two atomic bombings against the cities of Hiroshima and Nagasaki in Japan, the first on August 6, 1945, and the second on August 9, 1945. These two events are the only use of nuclear weapons in war to date.For six months...
ending the Pacific War
Pacific War
The Pacific War, also sometimes called the Asia-Pacific War refers broadly to the parts of World War II that took place in the Pacific Ocean, its islands, and in East Asia, then called the Far East...
. An international team was dispatched to help work on the project. The Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
started development shortly thereafter with their own atomic bomb project
Soviet atomic bomb project
The Soviet project to develop an atomic bomb , was a clandestine research and development program began during and post-World War II, in the wake of the Soviet Union's discovery of the United States' nuclear project...
, and not long after that both countries developed even more powerful fusion weapons called "hydrogen bombs."
During the Cold War
Cold War
The Cold War was the continuing state from roughly 1946 to 1991 of political conflict, military tension, proxy wars, and economic competition between the Communist World—primarily the Soviet Union and its satellite states and allies—and the powers of the Western world, primarily the United States...
, the Soviet Union and United States each acquired nuclear weapons arsenals numbering in the thousands, placing many of them onto rocket
Rocket
A rocket is a missile, spacecraft, aircraft or other vehicle which obtains thrust from a rocket engine. In all rockets, the exhaust is formed entirely from propellants carried within the rocket before use. Rocket engines work by action and reaction...
s that could hit targets anywhere in the world. Currently there are at least nine countries with functional nuclear weapons. A considerable amount of international negotiating has focused on the threat of nuclear warfare
Nuclear warfare
Nuclear warfare, or atomic warfare, is a military conflict or political strategy in which nuclear weaponry is detonated on an opponent. Compared to conventional warfare, nuclear warfare can be vastly more destructive in range and extent of damage...
and the proliferation
Nuclear proliferation
Nuclear proliferation is a term now used to describe the spread of nuclear weapons, fissile material, and weapons-applicable nuclear technology and information, to nations which are not recognized as "Nuclear Weapon States" by the Treaty on the Nonproliferation of Nuclear Weapons, also known as the...
of nuclear weapons to new nations or groups.
There have been (at least) four major false alarms, the most recent in 1995, that resulted in the activation of either the US's or Russia's nuclear attack early warning protocols.
Physics and politics in the 1930s
- See the main articles at History of physicsHistory of physicsAs forms of science historically developed out of philosophy, physics was originally referred to as natural philosophy, a term describing a field of study concerned with "the workings of nature".-Early history:...
, Nazi GermanyNazi GermanyNazi Germany , also known as the Third Reich , but officially called German Reich from 1933 to 1943 and Greater German Reich from 26 June 1943 onward, is the name commonly used to refer to the state of Germany from 1933 to 1945, when it was a totalitarian dictatorship ruled by...
and World War IIWorld War IIWorld War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
.
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
was revolutionised with developments in the understanding of the nature of atom
Atom
The atom is a basic unit of matter that consists of a dense central nucleus surrounded by a cloud of negatively charged electrons. The atomic nucleus contains a mix of positively charged protons and electrically neutral neutrons...
s. In 1898, French physicist Pierre Curie
Pierre Curie
Pierre Curie was a French physicist, a pioneer in crystallography, magnetism, piezoelectricity and radioactivity, and Nobel laureate. He was the son of Dr. Eugène Curie and Sophie-Claire Depouilly Curie ...
had discovered that pitchblende
Uraninite
Uraninite is a radioactive, uranium-rich mineral and ore with a chemical composition that is largely UO2, but also contains UO3 and oxides of lead, thorium, and rare earth elements...
, an ore of uranium
Uranium
Uranium is a silvery-white metallic chemical element in the actinide series of the periodic table, with atomic number 92. It is assigned the chemical symbol U. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons...
, contained a substance—which they named radium
Radium
Radium is a chemical element with atomic number 88, represented by the symbol Ra. Radium is an almost pure-white alkaline earth metal, but it readily oxidizes on exposure to air, becoming black in color. All isotopes of radium are highly radioactive, with the most stable isotope being radium-226,...
—that emitted large amounts of radioactivity. This raised hopes among scientists and laymen that the elements around us could contain tremendous amounts of unseen energy, waiting to be harnessed.
Experiments by Ernest Rutherford
Ernest Rutherford
Ernest Rutherford, 1st Baron Rutherford of Nelson OM, FRS was a New Zealand-born British chemist and physicist who became known as the father of nuclear physics...
in 1911 indicated that the vast majority of an atom's mass
Atomic mass
The atomic mass is the mass of a specific isotope, most often expressed in unified atomic mass units. The atomic mass is the total mass of protons, neutrons and electrons in a single atom....
was contained in a very small nucleus
Atomic nucleus
The nucleus is the very dense region consisting of protons and neutrons at the center of an atom. It was discovered in 1911, as a result of Ernest Rutherford's interpretation of the famous 1909 Rutherford experiment performed by Hans Geiger and Ernest Marsden, under the direction of Rutherford. The...
at its core, made up of proton
Proton
The proton is a subatomic particle with the symbol or and a positive electric charge of 1 elementary charge. One or more protons are present in the nucleus of each atom, along with neutrons. The number of protons in each atom is its atomic number....
s, surrounded by a web of electron
Electron
The electron is a subatomic particle with a negative elementary electric charge. It has no known components or substructure; in other words, it is generally thought to be an elementary particle. An electron has a mass that is approximately 1/1836 that of the proton...
s. In 1932, James Chadwick
James Chadwick
Sir James Chadwick CH FRS was an English Nobel laureate in physics awarded for his discovery of the neutron....
discovered that the nucleus contained another particle, the neutron
Neutron
The neutron is a subatomic hadron particle which has the symbol or , no net electric charge and a mass slightly larger than that of a proton. With the exception of hydrogen, nuclei of atoms consist of protons and neutrons, which are therefore collectively referred to as nucleons. The number of...
, and in the same year John Cockcroft
John Cockcroft
Sir John Douglas Cockcroft OM KCB CBE FRS was a British physicist. He shared the Nobel Prize in Physics for splitting the atomic nucleus with Ernest Walton, and was instrumental in the development of nuclear power....
and Ernest Walton
Ernest Walton
Ernest Thomas Sinton Walton was an Irish physicist and Nobel laureate for his work with John Cockcroft with "atom-smashing" experiments done at Cambridge University in the early 1930s, and so became the first person in history to artificially split the atom, thus ushering the nuclear age...
"split the atom" for the first time, the first occasion on which an atomic nucleus of one element had been successfully changed to a different nucleus by artificial means.
In 1934 the idea of chain reaction via neutron was proposed by Leó Szilárd
Leó Szilárd
Leó Szilárd was an Austro-Hungarian physicist and inventor who conceived the nuclear chain reaction in 1933, patented the idea of a nuclear reactor with Enrico Fermi, and in late 1939 wrote the letter for Albert Einstein's signature that resulted in the Manhattan Project that built the atomic bomb...
, who patented the idea of the atomic bomb. The patent was assigned by him to the Admiralty
Admiralty
The Admiralty was formerly the authority in the Kingdom of England, and later in the United Kingdom, responsible for the command of the Royal Navy...
(the controlling organisation for Britain's Royal Navy
Royal Navy
The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...
) in 1936, this 'sleight of hand' being necessary to prevent wider publication of the idea, as an Admiralty patent could be covered by the Official Secrets Act. In a very real sense, Szilárd was the father of the atomic bomb academically.
In 1934, French physicists Irène
Irène Joliot-Curie
Irène Joliot-Curie was a French scientist, the daughter of Marie Skłodowska-Curie and Pierre Curie and the wife of Frédéric Joliot-Curie. Jointly with her husband, Joliot-Curie was awarded the Nobel Prize for chemistry in 1935 for their discovery of artificial radioactivity. This made the Curies...
and Frédéric Joliot-Curie
Frédéric Joliot-Curie
Jean Frédéric Joliot-Curie , born Jean Frédéric Joliot, was a French physicist and Nobel laureate.-Early years:...
discovered that artificial radioactivity could be induced in stable elements by bombarding them with alpha particle
Alpha particle
Alpha particles consist of two protons and two neutrons bound together into a particle identical to a helium nucleus, which is classically produced in the process of alpha decay, but may be produced also in other ways and given the same name...
s, and in the same year Italian physicist Enrico Fermi
Enrico Fermi
Enrico Fermi was an Italian-born, naturalized American physicist particularly known for his work on the development of the first nuclear reactor, Chicago Pile-1, and for his contributions to the development of quantum theory, nuclear and particle physics, and statistical mechanics...
reported similar results when bombarding uranium with neutrons.
In December 1938, the German chemists Otto Hahn
Otto Hahn
Otto Hahn FRS was a German chemist and Nobel laureate, a pioneer in the fields of radioactivity and radiochemistry. He is regarded as "the father of nuclear chemistry". Hahn was a courageous opposer of Jewish persecution by the Nazis and after World War II he became a passionate campaigner...
and Fritz Strassmann
Fritz Strassmann
Friedrich Wilhelm "Fritz" Strassmann was a German chemist who, with Otto Hahn in 1938, identified barium in the residue after bombarding uranium with neutrons, which led to the interpretation of their results as being from nuclear fission...
sent a manuscript to Naturwissenschaften
Die Naturwissenschaften
Naturwissenschaften is a monthly peer-reviewed scientific journal published by Springer on behalf of several learned societies.- History :...
reporting they had detected the element barium
Barium
Barium is a chemical element with the symbol Ba and atomic number 56. It is the fifth element in Group 2, a soft silvery metallic alkaline earth metal. Barium is never found in nature in its pure form due to its reactivity with air. Its oxide is historically known as baryta but it reacts with...
after bombarding uranium
Uranium
Uranium is a silvery-white metallic chemical element in the actinide series of the periodic table, with atomic number 92. It is assigned the chemical symbol U. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons...
with neutrons; Lise Meitner
Lise Meitner
Lise Meitner FRS was an Austrian-born, later Swedish, physicist who worked on radioactivity and nuclear physics. Meitner was part of the team that discovered nuclear fission, an achievement for which her colleague Otto Hahn was awarded the Nobel Prize...
and her nephew Otto Robert Frisch
Otto Robert Frisch
Otto Robert Frisch , Austrian-British physicist. With his collaborator Rudolf Peierls he designed the first theoretical mechanism for the detonation of an atomic bomb in 1940.- Overview :...
correctly interpreted these results as being nuclear fission
Nuclear fission
In nuclear physics and nuclear chemistry, nuclear fission is a nuclear reaction in which the nucleus of an atom splits into smaller parts , often producing free neutrons and photons , and releasing a tremendous amount of energy...
. Frisch confirmed this experimentally on January 13, 1939.
Even before it was published, Meitner’s and Frisch’s interpretation of the work of Hahn and Strassmann crossed the Atlantic Ocean with Niels Bohr
Niels Bohr
Niels Henrik David Bohr was a Danish physicist who made foundational contributions to understanding atomic structure and quantum mechanics, for which he received the Nobel Prize in Physics in 1922. Bohr mentored and collaborated with many of the top physicists of the century at his institute in...
, who was to lecture at Princeton University
Princeton University
Princeton University is a private research university located in Princeton, New Jersey, United States. The school is one of the eight universities of the Ivy League, and is one of the nine Colonial Colleges founded before the American Revolution....
. Isidor Isaac Rabi
Isidor Isaac Rabi
Isidor Isaac Rabi was a Galician-born American physicist and Nobel laureate recognized in 1944 for his discovery of nuclear magnetic resonance.-Early years:...
and Willis Lamb
Willis Lamb
Willis Eugene Lamb, Jr. was an American physicist who won the Nobel Prize in Physics in 1955 together with Polykarp Kusch "for his discoveries concerning the fine structure of the hydrogen spectrum". Lamb and Kusch were able to precisely determine certain electromagnetic properties of the electron...
, two Columbia University
Columbia University
Columbia University in the City of New York is a private, Ivy League university in Manhattan, New York City. Columbia is the oldest institution of higher learning in the state of New York, the fifth oldest in the United States, and one of the country's nine Colonial Colleges founded before the...
physicists working at Princeton, heard the news and carried it back to Columbia. Rabi said he told Fermi; Fermi gave credit to Lamb. Bohr soon thereafter went from Princeton to Columbia to see Fermi. Not finding Fermi in his office, Bohr went down to the cyclotron area and found Herbert Anderson. Bohr grabbed him by the shoulder and said: “Young man, let me explain to you about something new and exciting in physics.”
It was clear to a number of scientists at Columbia that they should try to detect the energy released in the nuclear fission of uranium from neutron bombardment. On January 25, 1939 an experimental team at Columbia University conducted the first nuclear fission experiment in the United States in the basement of Pupin Hall
Pupin Hall
Pupin Physics Laboratories, also known as Pupin Hall is home to the physics and astronomy departments of the Columbia University in New York City and a National Historic Landmark...
. The team members were Herbert L. Anderson
Herbert L. Anderson
Herbert Lawrence Anderson was an American nuclear physicist who contributed to the Manhattan Project. He was also a member of the team which made the first demonstration of nuclear fission in the United States, in the basement of Pupin Hall at Columbia University. He participated in the first...
, Eugene T. Booth
Eugene T. Booth
Eugene Theodore Booth was an American nuclear physicist. He was a member of the historic Columbia University team which made the first demonstration of nuclear fission in the United States. During the Manhattan Project, he worked on gaseous diffusion for isotope separation...
, John R. Dunning
John R. Dunning
John Ray Dunning was an American physicist who played key roles in the development of the atomic bomb. He specialized in neutron physics and did pioneering work in gaseous diffusion for isotope separation...
, Enrico Fermi
Enrico Fermi
Enrico Fermi was an Italian-born, naturalized American physicist particularly known for his work on the development of the first nuclear reactor, Chicago Pile-1, and for his contributions to the development of quantum theory, nuclear and particle physics, and statistical mechanics...
, G. Norris Glasoe
G. N. Glasoe
G. Norris Glasoe was an American nuclear physicist. He was a member of the Columbia University team which was the first in the United States to verify the European discovery of the nuclear fission of uranium via neutron bombardment. During World War II, he worked at the MIT Radiation Laboratory...
, and Francis G. Slack
Francis G. Slack
Francis Goddard Slack was an American physicist. He was a physics teacher, researcher, and administrator in academia who was renowned for placing equal emphasis on teaching and on research.-Education:...
.
As Germany
Nazi Germany
Nazi Germany , also known as the Third Reich , but officially called German Reich from 1933 to 1943 and Greater German Reich from 26 June 1943 onward, is the name commonly used to refer to the state of Germany from 1933 to 1945, when it was a totalitarian dictatorship ruled by...
occupied Czechoslovakia
Czechoslovakia
Czechoslovakia or Czecho-Slovakia was a sovereign state in Central Europe which existed from October 1918, when it declared its independence from the Austro-Hungarian Empire, until 1992...
in 1938 and then the German army marched into Poland
Poland
Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...
in 1939, beginning World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
, many of Europe's top physicists had already begun to flee from the imminent conflict. Scientists on both sides of the conflict were well aware of the possibility of utilizing nuclear fission as a weapon, but at the time no one was quite sure how it could be done. In the early years of the war, physicists abruptly stopped publishing on the topic of fission, an act of self-censorship to keep the opposing side from gaining any advantage.
From Los Alamos to Hiroshima
Allies of World War II
The Allies of World War II were the countries that opposed the Axis powers during the Second World War . Former Axis states contributing to the Allied victory are not considered Allied states...
nations were concerned that Germany might have its own project
German nuclear energy project
The German nuclear energy project, , was an attempted clandestine scientific effort led by Germany to develop and produce the atomic weapons during the events involving the World War II...
to develop fission-based weapons. Organized research first began in Britain as part of the "Tube Alloys
Tube Alloys
Tube Alloys was the code-name for the British nuclear weapon directorate during World War II, when the development of nuclear weapons was kept at such a high level of secrecy that it had to be referred to by code even in the highest circles of government...
" project, and in the United States a small amount of funding was given for research into uranium weapons, starting in 1939 with the Uranium Committee under Lyman James Briggs
Lyman James Briggs
Lyman James Briggs was an American engineer, physicist and administrator. He was a distinguished director of the National Bureau of Standards during the Great Depression and chairman of the Uranium Committee before America entered the Second World War...
.
At the urging of British scientists who had made crucial calculations indicating that a fission weapon could be completed within only a few years, by 1941 the project had been wrested into better bureaucratic hands, and in 1942 came under the auspices of a Military Policy Committee led by General Leslie Groves
Leslie Groves
Lieutenant General Leslie Richard Groves, Jr. was a United States Army Corps of Engineers officer who oversaw the construction of the Pentagon and directed the Manhattan Project that developed the atomic bomb during World War II. As the son of a United States Army chaplain, Groves lived at a...
. This was known as the Manhattan Project
Manhattan Project
The Manhattan Project was a research and development program, led by the United States with participation from the United Kingdom and Canada, that produced the first atomic bomb during World War II. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the US Army...
.
Its scientific team led by the American physicist Robert Oppenheimer
Robert Oppenheimer
Julius Robert Oppenheimer was an American theoretical physicist and professor of physics at the University of California, Berkeley. Along with Enrico Fermi, he is often called the "father of the atomic bomb" for his role in the Manhattan Project, the World War II project that developed the first...
, the project brought together the top scientific minds of the day, including many exiles from Europe, with the production power of American industry for the goal of producing fission-based explosive devices before Germany. Britain and the U.S. agreed to pool their resources and information for the project, but the other Allied power—the Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
—was not informed.
A massive industrial and scientific undertaking, the Manhattan Project involved many of the world's leading physicists in the scientific and development aspects. The U.S. made an unprecedented investment in the project, spread across more than 30 sites in the U.S. and Canada. They centralized scientific development at Los Alamos
Los Alamos National Laboratory
Los Alamos National Laboratory is a United States Department of Energy national laboratory, managed and operated by Los Alamos National Security , located in Los Alamos, New Mexico...
, a secret laboratory that was previously a small ranch school near Santa Fe
Santa Fe, New Mexico
Santa Fe is the capital of the U.S. state of New Mexico. It is the fourth-largest city in the state and is the seat of . Santa Fe had a population of 67,947 in the 2010 census...
, New Mexico
New Mexico
New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...
.
Uranium appears in nature primarily in two isotopes: uranium-238
Uranium-238
Uranium-238 is the most common isotope of uranium found in nature. It is not fissile, but is a fertile material: it can capture a slow neutron and after two beta decays become fissile plutonium-239...
and uranium-235
Uranium-235
- References :* .* DOE Fundamentals handbook: Nuclear Physics and Reactor theory , .* A piece of U-235 the size of a grain of rice can produce energy equal to that contained in three tons of coal or fourteen barrels of oil. -External links:* * * one of the earliest articles on U-235 for the...
. When the nucleus of uranium-235 absorbs a neutron, it undergoes nuclear fission, splitting into two "fission products" and releasing energy and, on average, 2.5 neutrons. Uranium-238, on the other hand, absorbs neutrons but does not split, effectively putting a stop to any ongoing fission reaction.
Scientists discovered that an atomic bomb based on uranium would require at least 80% pure uranium-235, otherwise the presence of uranium-238 would quickly curtail the nuclear chain reaction
Nuclear chain reaction
A nuclear chain reaction occurs when one nuclear reaction causes an average of one or more nuclear reactions, thus leading to a self-propagating number of these reactions. The specific nuclear reaction may be the fission of heavy isotopes or the fusion of light isotopes...
. The team of scientists working at the Manhattan Project quickly realized that one of the largest problems was how to remove uranium-235 from natural uranium, which was composed of 99.3% uranium-238.
They developed two methods during the wartime project, which both took advantage of the fact that uranium-238 has a slightly greater atomic mass than uranium-235: electromagnetic separation and gaseous diffusion
Gaseous diffusion
Gaseous diffusion is a technology used to produce enriched uranium by forcing gaseous uranium hexafluoride through semi-permeable membranes. This produces a slight separation between the molecules containing uranium-235 and uranium-238 . By use of a large cascade of many stages, high separations...
—methods that separated isotopes based on their differing weights. Another secret site was erected at rural Oak Ridge, Tennessee
Oak Ridge, Tennessee
Oak Ridge is a city in Anderson and Roane counties in the eastern part of the U.S. state of Tennessee, about west of Knoxville. Oak Ridge's population was 27,387 at the 2000 census...
, for the large-scale production and purification of the rare isotope, which required considerable investment. At the time, K-25
K-25
K-25 is a former uranium enrichment facility of the Manhattan Project which used the gaseous diffusion method. The plant is located in Oak Ridge, Tennessee, on the southwestern end of the Oak Ridge Reservation.-History:...
, one of the Oak Ridge facilities, was the world's largest factory under one roof. The Oak Ridge site employed tens of thousands of employees at its peak, most of whom had no idea what they were working on.
Neptunium
Neptunium is a chemical element with the symbol Np and atomic number 93. A radioactive metal, neptunium is the first transuranic element and belongs to the actinide series. Its most stable isotope, 237Np, is a by-product of nuclear reactors and plutonium production and it can be used as a...
-239, and finally the relatively stable plutonium
Plutonium
Plutonium is a transuranic radioactive chemical element with the chemical symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air, forming a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation...
-239, an element that does not exist in nature. Plutonium is also fissile
Fissile
In nuclear engineering, a fissile material is one that is capable of sustaining a chain reaction of nuclear fission. By definition, fissile materials can sustain a chain reaction with neutrons of any energy. The predominant neutron energy may be typified by either slow neutrons or fast neutrons...
and can be used to create a fission reaction, and after Enrico Fermi
Enrico Fermi
Enrico Fermi was an Italian-born, naturalized American physicist particularly known for his work on the development of the first nuclear reactor, Chicago Pile-1, and for his contributions to the development of quantum theory, nuclear and particle physics, and statistical mechanics...
achieved the world's first sustained and controlled nuclear chain reaction in the creation of the first "atomic pile"—a primitive nuclear reactor
Nuclear reactor
A nuclear reactor is a device to initiate and control a sustained nuclear chain reaction. Most commonly they are used for generating electricity and for the propulsion of ships. Usually heat from nuclear fission is passed to a working fluid , which runs through turbines that power either ship's...
—in a basement at the University of Chicago
University of Chicago
The University of Chicago is a private research university in Chicago, Illinois, USA. It was founded by the American Baptist Education Society with a donation from oil magnate and philanthropist John D. Rockefeller and incorporated in 1890...
, massive reactors were secretly created at what is now known as Hanford Site
Hanford Site
The Hanford Site is a mostly decommissioned nuclear production complex on the Columbia River in the U.S. state of Washington, operated by the United States federal government. The site has been known by many names, including Hanford Works, Hanford Engineer Works or HEW, Hanford Nuclear Reservation...
in Washington State – using water from the Columbia River
Columbia River
The Columbia River is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, Canada, flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state...
in the cooling process – to transform uranium-238 into plutonium for a bomb.
For a fission weapon to operate, there must be a critical mass—the amount needed for a self-sustaining nuclear chain reaction—of fissile material bombarded with neutrons at any one time. The simplest form of nuclear weapon is a gun-type fission weapon
Gun-type fission weapon
Gun-type fission weapons are fission-based nuclear weapons whose design assembles their fissile material into a supercritical mass by the use of the "gun" method: shooting one piece of sub-critical material into another...
, where a sub-critical mass of fissile material (such as uranium-235) would be shot at another sub-critical mass of fissile material. The result would be a super-critical mass that, when bombarded with neutrons, would undergo fission at a rapid rate and create the desired explosion. The weapons envisaged in 1942 were the two gun-type weapons, Little Boy
Little Boy
"Little Boy" was the codename of the atomic bomb dropped on Hiroshima on August 6, 1945 by the Boeing B-29 Superfortress Enola Gay, piloted by Colonel Paul Tibbets of the 393rd Bombardment Squadron, Heavy, of the United States Army Air Forces. It was the first atomic bomb to be used as a weapon...
(uranium
Uranium
Uranium is a silvery-white metallic chemical element in the actinide series of the periodic table, with atomic number 92. It is assigned the chemical symbol U. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons...
) and Thin Man
Thin Man nuclear bomb
The "Thin Man" nuclear bomb was a proposed plutonium gun-type nuclear bomb which the United States was developing during the Manhattan Project...
(plutonium
Plutonium
Plutonium is a transuranic radioactive chemical element with the chemical symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air, forming a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation...
), and the Fat Man
Fat Man
"Fat Man" is the codename for the atomic bomb that was detonated over Nagasaki, Japan, by the United States on August 9, 1945. It was the second of the only two nuclear weapons to be used in warfare to date , and its detonation caused the third man-made nuclear explosion. The name also refers more...
plutonium implosion bomb.
In early 1943 Oppenheimer determined that two projects should proceed forwards: the "Thin Man" project (plutonium gun) and the "Fat Man" project (plutonium implosion). The plutonium gun was to receive the bulk of the research effort, as it was the project with the most uncertainty involved. It was assumed that the uranium gun-type bomb could then be adapted from it.
Spontaneous fission
Spontaneous fission is a form of radioactive decay characteristic of very heavy isotopes. Because the nuclear binding energy reaches a maximum at a nuclear mass greater than about 60 atomic mass units , spontaneous breakdown into smaller nuclei and single particles becomes possible at heavier masses...
to a very small extent, due to the presence of impurities of the Pu-240 isotope. If such plutonium were used in a "gun assembly," the chain reaction would start in the split seconds before the critical mass was assembled, blowing the weapon apart before it would have any great effect (this is known as a fizzle).
As a result, development of Fat Man
Fat Man
"Fat Man" is the codename for the atomic bomb that was detonated over Nagasaki, Japan, by the United States on August 9, 1945. It was the second of the only two nuclear weapons to be used in warfare to date , and its detonation caused the third man-made nuclear explosion. The name also refers more...
(the implosion bomb) was given high priority. Chemical explosives were used to implode a sub-critical sphere of plutonium, thus increasing its density and making it into a critical mass. The difficulties with implosion centered on the problem of making the chemical explosives deliver a perfectly uniform shock wave upon the plutonium sphere— if it were even slightly asymmetric, the weapon would fizzle (which would be expensive, messy, and not a very effective military device). This problem was circumvented by the use of hydrodynamic "lenses"—explosive materials of differing densities—which would focus the blast waves inside the imploding sphere, akin to the way in which an optical lens focuses light rays.
After D-Day
D-Day
D-Day is a term often used in military parlance to denote the day on which a combat attack or operation is to be initiated. "D-Day" often represents a variable, designating the day upon which some significant event will occur or has occurred; see Military designation of days and hours for similar...
, General Groves ordered a team of scientists—Project Alsos
Alsos
Alsos may refer to:*Alsos Forest , a natural park in Nicosia , Cyprus*Operation Alsos, an effort by the Allies during World War II*Russian Alsos*Alsos, a village in the municipality of Sympoliteia in the Achaea prefecture in Greece*Alsos Nea Smyrni...
—to follow eastward-moving victorious Allied troops into Europe to assess the status of the German nuclear program (and to prevent the westward-moving Russians from gaining any materials or scientific manpower). They concluded that, while Germany had an atomic bomb program headed by Werner Heisenberg
Werner Heisenberg
Werner Karl Heisenberg was a German theoretical physicist who made foundational contributions to quantum mechanics and is best known for asserting the uncertainty principle of quantum theory...
, the government had not made a significant investment in the project, and it had been nowhere near success.
Historians claim to have found a rough schematic showing a Nazi nuclear bomb. Research was conducted in the German nuclear energy project
German nuclear energy project
The German nuclear energy project, , was an attempted clandestine scientific effort led by Germany to develop and produce the atomic weapons during the events involving the World War II...
. In March 1945, a German scientific team was directed by the physicist Kurt Diebner
Kurt Diebner
Kurt Diebner was a German nuclear physicist who is well known for directing and administrating the German nuclear energy project, a secretive program aiming to built weapon of mass destruction for the Nazi Germany during the course of World War II...
to develop a primitive nuclear device in Ohrdruf
Ohrdruf
Ohrdruf is a small town in the German federal state of Thuringia. It lies some 30 km southwest of Erfurt.-Medieval settling:Ohrdruf was founded in 724–726 by Saint Boniface, as the site of the first monastery in Thuringia, dedicated to Saint Michael. It was the first of several religious...
, Thuringia
Thuringia
The Free State of Thuringia is a state of Germany, located in the central part of the country.It has an area of and 2.29 million inhabitants, making it the sixth smallest by area and the fifth smallest by population of Germany's sixteen states....
. Last ditch research was conducted in an experimental nuclear reactor at Haigerloch
Haigerloch
-Geography:-Geographical situation:Haigerloch lies at between 430 and 550 metres elevation in the valley of the Eyach, which forms two loops in a steep shelly limestone valley...
.
At the time of the unconditional surrender of Germany on May 8, 1945, the Manhattan Project was still months away from producing a working weapon. That April, after the death of American President Franklin D. Roosevelt
Franklin D. Roosevelt
Franklin Delano Roosevelt , also known by his initials, FDR, was the 32nd President of the United States and a central figure in world events during the mid-20th century, leading the United States during a time of worldwide economic crisis and world war...
, former Vice-President Harry S. Truman
Harry S. Truman
Harry S. Truman was the 33rd President of the United States . As President Franklin D. Roosevelt's third vice president and the 34th Vice President of the United States , he succeeded to the presidency on April 12, 1945, when President Roosevelt died less than three months after beginning his...
was told about the secret wartime project for the first time.
Because of the difficulties in making a working plutonium bomb
Bomb
A bomb is any of a range of explosive weapons that only rely on the exothermic reaction of an explosive material to provide an extremely sudden and violent release of energy...
, it was decided that there should be a test of the weapon, and Truman wanted to know for certain if it would work before his meeting with Stalin
Joseph Stalin
Joseph Vissarionovich Stalin was the Premier of the Soviet Union from 6 May 1941 to 5 March 1953. He was among the Bolshevik revolutionaries who brought about the October Revolution and had held the position of first General Secretary of the Communist Party of the Soviet Union's Central Committee...
at an upcoming conference
Potsdam Conference
The Potsdam Conference was held at Cecilienhof, the home of Crown Prince Wilhelm Hohenzollern, in Potsdam, occupied Germany, from 16 July to 2 August 1945. Participants were the Soviet Union, the United Kingdom, and the United States...
on the future of postwar Europe. On July 16, 1945, in the desert north of Alamogordo, New Mexico
New Mexico
New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...
, the first nuclear test took place, code-named "Trinity
Trinity test
Trinity was the code name of the first test of a nuclear weapon. This test was conducted by the United States Army on July 16, 1945, in the Jornada del Muerto desert about 35 miles southeast of Socorro, New Mexico, at the new White Sands Proving Ground, which incorporated the Alamogordo Bombing...
," using a device nicknamed "the Gadget." The test, a plutonium implosion type device, released the equivalent of 19 kilotons of TNT
TNT equivalent
TNT equivalent is a method of quantifying the energy released in explosions. The ton of TNT is a unit of energy equal to 4.184 gigajoules, which is approximately the amount of energy released in the detonation of one ton of TNT...
, far more powerful than any weapon ever used before. The news of the test's success was rushed to Truman, who used it as leverage at the Potsdam conference, held near Berlin
Berlin
Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...
.
Euphemism
A euphemism is the substitution of a mild, inoffensive, relatively uncontroversial phrase for another more frank expression that might offend or otherwise suggest something unpleasant to the audience...
term for populated cities), Truman ordered the use of the weapons on Japanese cities, hoping it would send a strong message that would end in the capitulation of the Japanese leadership and avoid a lengthy invasion of the islands.
There were suggestions to drop the atomic bomb on Tokyo
Tokyo
, ; officially , is one of the 47 prefectures of Japan. Tokyo is the capital of Japan, the center of the Greater Tokyo Area, and the largest metropolitan area of Japan. It is the seat of the Japanese government and the Imperial Palace, and the home of the Japanese Imperial Family...
, the capital of Japan, but concerns about Tokyo's cultural heritage forced a reconsideration of this plan. On May 10–11, 1945, the Target Committee at Los Alamos, led by Oppenheimer, recommended Kyoto, Hiroshima, Yokohama, and the arsenal at Kokura as possible targets. On August 6, 1945, a uranium-based weapon, "Little Boy
Little Boy
"Little Boy" was the codename of the atomic bomb dropped on Hiroshima on August 6, 1945 by the Boeing B-29 Superfortress Enola Gay, piloted by Colonel Paul Tibbets of the 393rd Bombardment Squadron, Heavy, of the United States Army Air Forces. It was the first atomic bomb to be used as a weapon...
," was detonated above the Japanese city of Hiroshima
Hiroshima
is the capital of Hiroshima Prefecture, and the largest city in the Chūgoku region of western Honshu, the largest island of Japan. It became best known as the first city in history to be destroyed by a nuclear weapon when the United States Army Air Forces dropped an atomic bomb on it at 8:15 A.M...
. Three days later, a plutonium-based weapon, "Fat Man
Fat Man
"Fat Man" is the codename for the atomic bomb that was detonated over Nagasaki, Japan, by the United States on August 9, 1945. It was the second of the only two nuclear weapons to be used in warfare to date , and its detonation caused the third man-made nuclear explosion. The name also refers more...
," was detonated above the city of Nagasaki. The atomic bombs killed at least one hundred thousand
Atomic bombings of Hiroshima and Nagasaki
During the final stages of World War II in 1945, the United States conducted two atomic bombings against the cities of Hiroshima and Nagasaki in Japan, the first on August 6, 1945, and the second on August 9, 1945. These two events are the only use of nuclear weapons in war to date.For six months...
Japanese outright, most of them civilians, with the heat, radiation, and blast effects.
Many tens of thousands would later die of radiation sickness and related cancers. Truman promised a "rain of ruin" if Japan did not surrender immediately, threatening to eliminate Japanese cities, one by one; Japan surrendered on August 15. Truman's threat was in fact a bluff
Deception
Deception, beguilement, deceit, bluff, mystification, bad faith, and subterfuge are acts to propagate beliefs that are not true, or not the whole truth . Deception can involve dissimulation, propaganda, and sleight of hand. It can employ distraction, camouflage or concealment...
, since the US had but one remaining uranium-gun type bomb completed.
Soviet atomic bomb project
- See the main article at Soviet atomic bomb projectSoviet atomic bomb projectThe Soviet project to develop an atomic bomb , was a clandestine research and development program began during and post-World War II, in the wake of the Soviet Union's discovery of the United States' nuclear project...
.
The Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
was not invited to share in the new weapons developed by the United States and the other Allies. During the war, information had been pouring in from a number of volunteer spies involved with the Manhattan Project (known in Soviet cables under the code-name of Enormoz), and the Soviet nuclear physicist Igor Kurchatov
Igor Kurchatov
Igor Vasilyevich Kurchatov , was a Soviet nuclear physicist who is widely known as the director of the Soviet atomic bomb project. Along with Georgy Flyorov and Andrei Sakharov, Kurchatov is widely remembered and dubbed as the "father of the Soviet atomic bomb" for his directorial role in the...
was carefully watching the Allied weapons development. It came as no surprise to Stalin when Truman had informed him at the Potsdam conference that he had a "powerful new weapon." Truman was shocked at Stalin's lack of interest.
The Soviet spies in the U.S. project were all volunteers and none were Russians. One of the most valuable, Klaus Fuchs
Klaus Fuchs
Klaus Emil Julius Fuchs was a German theoretical physicist and atomic spy who in 1950 was convicted of supplying information from the American, British and Canadian atomic bomb research to the USSR during and shortly after World War II...
, was a German émigré theoretical physicist who had been a part in the early British nuclear efforts and had been part of the UK mission to Los Alamos during the war. Fuchs had been intimately involved in the development of the implosion weapon, and passed on detailed cross-sections of the "Trinity" device to his Soviet contacts. Other Los Alamos spies—none of whom knew each other—included Theodore Hall
Theodore Hall
Theodore Alvin Hall was an American physicist and an atomic spy for the Soviet Union, who, during his work on US efforts to develop the first atomic bomb during World War II , gave a detailed description of the "Fat Man" plutonium bomb, and of processes for purifying plutonium, to Soviet...
and David Greenglass
David Greenglass
David Greenglass was an atomic spy for the Soviet Union who worked in the Manhattan project. He was the brother of Ethel Rosenberg.-Biography:...
. The information was kept but not acted upon, as Russia was still too busy fighting the war in Europe to devote resources to this new project.
In the years immediately after World War II, the issue of who should control atomic weapons became a major international point of contention. Many of the Los Alamos scientists who had built the bomb began to call for "international control of atomic energy," often calling for either control by transnational organizations or the purposeful distribution of weapons information to all superpowers, but due to a deep distrust of the intentions of the Soviet Union, both in postwar Europe and in general, the policy-makers of the United States worked to attempt to secure an American nuclear monopoly.
A half-hearted plan for international control was proposed at the newly formed United Nations
United Nations
The United Nations is an international organization whose stated aims are facilitating cooperation in international law, international security, economic development, social progress, human rights, and achievement of world peace...
by Bernard Baruch
Bernard Baruch
Bernard Mannes Baruch was an American financier, stock-market speculator, statesman, and political consultant. After his success in business, he devoted his time toward advising U.S. Presidents Woodrow Wilson and Franklin D. Roosevelt on economic matters and became a philanthropist.-Early life...
("The Baruch Plan
Baruch Plan
The Baruch Plan was a proposal by the United States government, written largely by Bernard Baruch but based on the Acheson–Lilienthal Report, to the United Nations Atomic Energy Commission in its first meeting in June 1946...
"), but it was clear both to American commentators—and to the Soviets—that it was an attempt primarily to stymie Russian nuclear efforts. The Soviets vetoed the plan, effectively ending any immediate postwar negotiations on atomic energy, and made overtures towards banning the use of atomic weapons in general.
All the while, the Soviets had put their full industrial and manpower might into the development of their own atomic weapons. The initial problem for the Soviets was primarily one of resources—they had not scouted out uranium resources in the Soviet Union and the U.S. had made deals to monopolise the largest known (and high purity) reserves in the Belgian Congo
Belgian Congo
The Belgian Congo was the formal title of present-day Democratic Republic of the Congo between King Leopold II's formal relinquishment of his personal control over the state to Belgium on 15 November 1908, and Congolese independence on 30 June 1960.-Congo Free State, 1884–1908:Until the latter...
. The USSR used penal labour
Penal labour
Penal labour is a form of unfree labour in which prisoners perform work, typically manual labour. The work may be light or hard, depending on the context. Forms of sentence which involve penal labour include penal servitude and imprisonment with hard labour...
to mine the old deposits in Czechoslovakia
Czechoslovakia
Czechoslovakia or Czecho-Slovakia was a sovereign state in Central Europe which existed from October 1918, when it declared its independence from the Austro-Hungarian Empire, until 1992...
—now an area under their control—and searched for other domestic deposits (which were eventually found).
Two days after the bombing of Nagasaki, the U.S. government released an official technical history of the Manhattan Project, authored by Princeton physicist Henry DeWolf Smyth
Henry DeWolf Smyth
Henry DeWolf "Harry" Smyth was an American physicist, diplomat, and bureaucrat who played a number of key roles in the early development of nuclear energy. Educated at Princeton University and the University of Cambridge, he was a faculty member in Princeton's Department of Physics from 1924 to...
, known colloquially as the Smyth Report
Smyth Report
The Smyth Report was the common name given to an administrative history written by physicist Henry DeWolf Smyth about the Allied World War II effort to develop the atomic bomb, the Manhattan Project...
. The sanitized summary of the wartime effort focused primarily on the production facilities and scale of investment, written in part to justify the wartime expenditure to the American public.
The Soviet program, under the suspicious watch of former NKVD
NKVD
The People's Commissariat for Internal Affairs was the public and secret police organization of the Soviet Union that directly executed the rule of power of the Soviets, including political repression, during the era of Joseph Stalin....
chief Lavrenty Beria (a participant and victor in Stalin's Great Purge
Great Purge
The Great Purge was a series of campaigns of political repression and persecution in the Soviet Union orchestrated by Joseph Stalin from 1936 to 1938...
of the 1930s), would use the Report as a blueprint, seeking to duplicate as much as possible the American effort. The "secret cities" used for the Soviet equivalents of Hanford and Oak Ridge literally vanished from the maps for decades to come.
At the Soviet equivalent of Los Alamos, Arzamas-16
Sarov
Sarov is a closed town in Nizhny Novgorod Oblast, Russia. Until 1995 it was known as Kremlyov ., while from 1946 to 1991 it was called Arzamas-16 . The town is off limits to foreigners as it is the Russian center for nuclear research. Population: -History:The history of the town can be divided...
, physicist Yuli Khariton led the scientific effort to develop the weapon. Beria distrusted his scientists, however, and he distrusted the carefully collected espionage information. As such, Beria assigned multiple teams of scientists to the same task without informing each team of the other's existence. If they arrived at different conclusions, Beria would bring them together for the first time and have them debate with their newfound counterparts. Beria used the espionage information as a way to double-check the progress of his scientists, and in his effort for duplication of the American project even rejected more efficient bomb designs in favor of ones that more closely mimicked the tried-and-true "Fat Man
Fat Man
"Fat Man" is the codename for the atomic bomb that was detonated over Nagasaki, Japan, by the United States on August 9, 1945. It was the second of the only two nuclear weapons to be used in warfare to date , and its detonation caused the third man-made nuclear explosion. The name also refers more...
" bomb used by the U.S. against Nagasaki.
Working under a stubborn and scientifically ignorant administrator, the Soviet scientists struggled on. On August 29, 1949, the effort brought its results, when the USSR tested its first fission bomb, dubbed "Joe-1" by the U.S., years ahead of American predictions. The news of the first Soviet bomb was announced to the world first by the United States, which had detected the nuclear fallout
Nuclear fallout
Fallout is the residual radioactive material propelled into the upper atmosphere following a nuclear blast, so called because it "falls out" of the sky after the explosion and shock wave have passed. It commonly refers to the radioactive dust and ash created when a nuclear weapon explodes...
it generated from its test site in Kazakhstan
Semipalatinsk Test Site
The Semipalatinsk Test Site was the primary testing venue for the Soviet Union's nuclear weapons. It is located on the steppe in northeast Kazakhstan , south of the valley of the Irtysh River...
.
The loss of the American monopoly on nuclear weapons marked the first tit-for-tat of the nuclear arms race
Nuclear arms race
The nuclear arms race was a competition for supremacy in nuclear warfare between the United States, the Soviet Union, and their respective allies during the Cold War...
. The response in the U.S. was one of apprehension, fear, and scapegoating, which would lead eventually into the Red-baiting tactics of McCarthyism
McCarthyism
McCarthyism is the practice of making accusations of disloyalty, subversion, or treason without proper regard for evidence. The term has its origins in the period in the United States known as the Second Red Scare, lasting roughly from the late 1940s to the late 1950s and characterized by...
. Yet recent information from unclassified Venona intercepts and the opening of the KGB archives after the fall of the Soviet Union show that the USSR had useful spies that helped their program, although none were identified by McCarthy. Before this, though, President Truman announced a decision to begin a crash program that would develop a far more powerful weapon than those the U.S. used against Japan: the hydrogen bomb.
The first thermonuclear weapons
The notion of using a fission weapon to ignite a process of nuclear fusionNuclear fusion
Nuclear fusion is the process by which two or more atomic nuclei join together, or "fuse", to form a single heavier nucleus. This is usually accompanied by the release or absorption of large quantities of energy...
can be dated back to 1942. At the first major theoretical conference on the development of an atomic bomb hosted by J. Robert Oppenheimer at the University of California, Berkeley
University of California, Berkeley
The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...
, participant Edward Teller
Edward Teller
Edward Teller was a Hungarian-American theoretical physicist, known colloquially as "the father of the hydrogen bomb," even though he did not care for the title. Teller made numerous contributions to nuclear and molecular physics, spectroscopy , and surface physics...
directed the majority of the discussion towards Enrico Fermi
Enrico Fermi
Enrico Fermi was an Italian-born, naturalized American physicist particularly known for his work on the development of the first nuclear reactor, Chicago Pile-1, and for his contributions to the development of quantum theory, nuclear and particle physics, and statistical mechanics...
's idea of a "Super" bomb that would use the same reactions that powered the Sun
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...
itself.
It was thought at the time that a fission weapon would be quite simple to develop and that perhaps work on a hydrogen bomb would be possible to complete before the end of the Second World War. However, in reality the problem of a "regular" atomic bomb was large enough to preoccupy the scientists for the next few years, much less the more speculative "Super." Only Teller continued working on the project—against the will of project leaders Oppenheimer and Hans Bethe
Hans Bethe
Hans Albrecht Bethe was a German-American nuclear physicist, and Nobel laureate in physics for his work on the theory of stellar nucleosynthesis. A versatile theoretical physicist, Bethe also made important contributions to quantum electrodynamics, nuclear physics, solid-state physics and...
.
After the atomic bombings of Japan, many scientists at Los Alamos
Los Alamos National Laboratory
Los Alamos National Laboratory is a United States Department of Energy national laboratory, managed and operated by Los Alamos National Security , located in Los Alamos, New Mexico...
rebelled against the notion of creating a weapon thousands of times more powerful than the first atomic bombs. For the scientists the question was in part technical—the weapon design was still quite uncertain and unworkable—and in part moral: such a weapon, they argued, could only be used against large civilian populations, and could thus only be used as a weapon of genocide.
Many scientists, such as Bethe, urged that the United States should not develop such weapons and set an example towards the Soviet Union. Promoters of the weapon, including Teller, Ernest Lawrence
Ernest Lawrence
Ernest Orlando Lawrence was an American physicist and Nobel Laureate, known for his invention, utilization, and improvement of the cyclotron atom-smasher beginning in 1929, based on his studies of the works of Rolf Widerøe, and his later work in uranium-isotope separation for the Manhattan Project...
, and Luis Alvarez
Luis Alvarez
Luis W. Alvarez was an American experimental physicist and inventor, who spent nearly all of his long professional career on the faculty of the University of California, Berkeley...
, argued that such a development was inevitable, and to deny such protection to the people of the United States—especially when the Soviet Union was likely to create such a weapon themselves—was itself an immoral and unwise act.
Oppenheimer, who was now head of the General Advisory Committee of the successor to the Manhattan Project, the Atomic Energy Commission
United States Atomic Energy Commission
The United States Atomic Energy Commission was an agency of the United States government established after World War II by Congress to foster and control the peace time development of atomic science and technology. President Harry S...
, presided over a recommendation against the development of the weapon. The reasons were in part because the success of the technology seemed limited at the time (and not worth the investment of resources to confirm whether this was so), and because Oppenheimer believed that the atomic forces of the United States would be more effective if they consisted of many large fission weapons (of which multiple bombs could be dropped on the same targets) rather than the large and unwieldy predictions of massive super bombs, for which there were a relatively limited amounts of targets of the size to warrant such a development.
Furthermore, were such weapons developed by both the U.S. and the USSR, they would be more effectively used against the U.S. than by it, as the U.S. had far more regions of dense industrial and civilian activity as targets for large weapons than the Soviet Union.
Teller pushed the notion further, and used the results of the boosted-fission "George
Operation Greenhouse
Operation Greenhouse was the fifth American nuclear test series, the second conducted in 1951 and the first to test principles that would lead to developing thermonuclear weapons . Conducted at the new Pacific Proving Ground, all of the devices were mounted in large steel towers, to simulate air...
" test (a boosted-fission device using a small amount of fusion fuel to boost the yield of a fission bomb) to confirm the fusion of heavy hydrogen elements before preparing for their first true multi-stage, Teller-Ulam hydrogen bomb
Teller-Ulam design
The Teller–Ulam design is the nuclear weapon design concept used in most of the world's nuclear weapons. It is colloquially referred to as "the secret of the hydrogen bomb" because it employs hydrogen fusion, though in most applications the bulk of its destructive energy comes from uranium fission,...
test. Many scientists initially against the weapon, such as Oppenheimer and Bethe, changed their previous opinions, seeing the development as being unstoppable.
The first fusion bomb was tested by the United States in Operation Ivy
Operation Ivy
Operation Ivy was the eighth series of American nuclear tests, coming after Tumbler-Snapper and before Upshot-Knothole. Its purpose was to help upgrade the U.S. arsenal of nuclear weapons in response to the Soviet nuclear weapons program...
on November 1, 1952, on Elugelab Island in the Enewetak (or Eniwetok) Atoll of the Marshall Islands
Marshall Islands
The Republic of the Marshall Islands , , is a Micronesian nation of atolls and islands in the middle of the Pacific Ocean, just west of the International Date Line and just north of the Equator. As of July 2011 the population was 67,182...
, code-named "Mike
Ivy Mike
Ivy Mike was the codename given to the first United States test of a thermonuclear weapon, in which a major part of the explosive yield came from nuclear fusion. It was detonated on November 1, 1952 by the United States at on Enewetak, an atoll in the Pacific Ocean, as part of Operation Ivy...
." "Mike" used liquid deuterium
Deuterium
Deuterium, also called heavy hydrogen, is one of two stable isotopes of hydrogen. It has a natural abundance in Earth's oceans of about one atom in of hydrogen . Deuterium accounts for approximately 0.0156% of all naturally occurring hydrogen in Earth's oceans, while the most common isotope ...
as its fusion fuel and a large fission weapon as its trigger. The device was a prototype design and not a deliverable weapon: standing over 20 ft (6 m) high and weighing at least 140,000 lb (64 t) (its refrigeration equipment added an additional 24000 lb (10,886.2 kg) as well), it could not have been dropped from even the largest planes.
Its explosion yielded 10.4 megatons
TNT equivalent
TNT equivalent is a method of quantifying the energy released in explosions. The ton of TNT is a unit of energy equal to 4.184 gigajoules, which is approximately the amount of energy released in the detonation of one ton of TNT...
of energy—over 450 times the power of the bomb dropped onto Nagasaki— and obliterated Elugelab
Elugelab
Elugelab was an island, part of the Enewetak atoll in the Marshall Islands. It was destroyed by the world's first test of a hydrogen bomb on 1 November 1952, as part of Operation Ivy...
, leaving an underwater crater 6240 ft (1.9 km) wide and 164 ft (50 m) deep where the island had once been. Truman had initially tried to create a media blackout about the test—hoping it would not become an issue in the upcoming presidential election—but on January 7, 1953, Truman announced the development of the hydrogen bomb to the world as hints and speculations of it were already beginning to emerge in the press.
Not to be outdone, the Soviet Union exploded its first thermonuclear device, designed by the physicist Andrei Sakharov
Andrei Sakharov
Andrei Dmitrievich Sakharov was a Soviet nuclear physicist, dissident and human rights activist. He earned renown as the designer of the Soviet Union's Third Idea, a codename for Soviet development of thermonuclear weapons. Sakharov was an advocate of civil liberties and civil reforms in the...
, on August 12, 1953, labeled "Joe-4" by the West. This created concern within the U.S. government and military, because, unlike "Mike," the Soviet device was a deliverable weapon, which the U.S. did not yet have. This first device though was arguably not a "true" hydrogen bomb, and could only reach explosive yields in the hundreds of kilotons (never reaching the megaton range of a "staged" weapon). Still, it was a powerful propaganda tool for the Soviet Union, and the technical differences were fairly oblique to the American public and politicians.
Following the "Mike" blast by less than a year, "Joe-4" seemed to validate claims that the bombs were inevitable and vindicate those who had supported the development of the fusion program. Coming during the height of McCarthyism
McCarthyism
McCarthyism is the practice of making accusations of disloyalty, subversion, or treason without proper regard for evidence. The term has its origins in the period in the United States known as the Second Red Scare, lasting roughly from the late 1940s to the late 1950s and characterized by...
, the effect was most pronounced by the security hearings in early 1954, which revoked former Los Alamos director Robert Oppenheimer's security clearance on the grounds that he was unreliable, had not supported the American hydrogen bomb program, and had made long-standing left-wing ties in the 1930s. Edward Teller participated in the hearing as the only major scientist to testify against Oppenheimer, resulting in his virtual expulsion from the physics community.
On February 28, 1954, the U.S. detonated its first deliverable thermonuclear weapon (which used isotopes of lithium
Lithium
Lithium is a soft, silver-white metal that belongs to the alkali metal group of chemical elements. It is represented by the symbol Li, and it has the atomic number 3. Under standard conditions it is the lightest metal and the least dense solid element. Like all alkali metals, lithium is highly...
as its fusion fuel), known as the "Shrimp" device of the "Castle Bravo
Castle Bravo
Castle Bravo was the code name given to the first U.S. test of a dry fuel thermonuclear hydrogen bomb device, detonated on March 1, 1954 at Bikini Atoll, Marshall Islands, as the first test of Operation Castle. Castle Bravo was the most powerful nuclear device ever detonated by the United States ,...
" test, at Bikini Atoll
Bikini Atoll
Bikini Atoll is an atoll, listed as a World Heritage Site, in the Micronesian Islands of the Pacific Ocean, part of Republic of the Marshall Islands....
, Marshall Islands
Marshall Islands
The Republic of the Marshall Islands , , is a Micronesian nation of atolls and islands in the middle of the Pacific Ocean, just west of the International Date Line and just north of the Equator. As of July 2011 the population was 67,182...
. The device yielded 15 megatons of energy, three times its expected yield, and became the worst radiological disaster in U.S. history. The combination of the unexpectedly large blast and poor weather conditions caused a cloud of radioactive nuclear fallout
Nuclear fallout
Fallout is the residual radioactive material propelled into the upper atmosphere following a nuclear blast, so called because it "falls out" of the sky after the explosion and shock wave have passed. It commonly refers to the radioactive dust and ash created when a nuclear weapon explodes...
to contaminate over 7000 square miles (18,129.9 km²), including Marshall Island natives and the crew of a Japanese fishing boat, as a snow-like mist. The contaminated islands were evacuated (and are still uninhabitable), but the natives received enough of a radioactive dose that they suffered far elevated levels of cancer
Cancer
Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...
and birth defects in the years to come.
The crew of the Japanese fishing boat, Lucky Dragon 5, returned to port suffering from radiation sickness
Radiation Sickness
Radiation Sickness is a VHS by the thrash metal band Nuclear Assault. The video is a recording of a concert at the Hammersmith Odeon, London in 1988. It was released in 1991...
and skin burns. Their cargo, many tons of contaminated fish, managed to enter into the market before the cause of their illness was determined. When a crew member died from the sickness and the full results of the contamination were made public by the U.S., Japanese concerns were reignited about the hazards of radiation and resulted in a boycott on eating fish (a main staple of the island country) for some weeks.
Nuclear warfare
Nuclear warfare, or atomic warfare, is a military conflict or political strategy in which nuclear weaponry is detonated on an opponent. Compared to conventional warfare, nuclear warfare can be vastly more destructive in range and extent of damage...
in the popular and military mind. With only fission bombs, nuclear war was something that possibly could be "limited." Dropped by planes and only able to destroy the most built up areas of major cities, it was possible for many to look at fission bombs as a technological extension of large-scale conventional bombing—such as the extensive firebombing
Firebombing
Firebombing is a bombing technique designed to damage a target, generally an urban area, through the use of fire, caused by incendiary devices, rather than from the blast effect of large bombs....
against Japan and Germany during World War II). Proponents brushed aside as grave exaggeration claims that such weapons could lead to worldwide death or harm.
Even in the decades before fission weapons, there had been speculation about the possibility for human beings to end all life on the planet, either by accident or purposeful maliciousness—but technology had not provided the capacity for such action. The great power of hydrogen bombs made world-wide annihilation possible.
The "Castle Bravo" incident itself raised a number of questions about the survivability of a nuclear war. Government scientists in both the U.S. and the USSR had insisted that fusion weapons, unlike fission weapons, were "cleaner," as fusion reactions did not produce the dangerously radioactive by-products of fission reactions. While technically true, this hid a more gruesome point: the last stage of a multi-staged hydrogen bomb often used the neutrons produced by the fusion reactions to induce fissioning in a jacket of natural uranium, and provided around half of the yield of the device itself.
This fission stage made fusion weapons considerably more "dirty" than they were made out to be. This was evident in the towering cloud of deadly fallout that followed the Bravo test. When the Soviet Union tested its first megaton device in 1955, the possibility of a limited nuclear war seemed even more remote in the public and political mind. Even cities and countries that were not direct targets would suffer fallout contamination. Extremely harmful fission products would disperse via normal weather patterns and embed in soil and water around the planet.
Speculation began to run towards what fallout and dust from a full-scale nuclear exchange would do to the world as a whole, rather than just cities and countries directly involved. In this way, the fate of the world was now tied to the fate of the bomb-wielding superpowers.
Deterrence and brinkmanship
- See the main articles at Nuclear testingNuclear testingNuclear weapons tests are experiments carried out to determine the effectiveness, yield and explosive capability of nuclear weapons. Throughout the twentieth century, most nations that have developed nuclear weapons have tested them...
, Nuclear strategyNuclear strategyNuclear strategy involves the development of doctrines and strategies for the production and use of nuclear weapons.As a sub-branch of military strategy, nuclear strategy attempts to match nuclear weapons as means to political ends...
, and Nuclear warfareNuclear warfareNuclear warfare, or atomic warfare, is a military conflict or political strategy in which nuclear weaponry is detonated on an opponent. Compared to conventional warfare, nuclear warfare can be vastly more destructive in range and extent of damage...
.
1950s
The 1950s or The Fifties was the decade that began on January 1, 1950 and ended on December 31, 1959. The decade was the sixth decade of the 20th century...
and the early 1960s
1960s
The 1960s was the decade that started on January 1, 1960, and ended on December 31, 1969. It was the seventh decade of the 20th century.The 1960s term also refers to an era more often called The Sixties, denoting the complex of inter-related cultural and political trends across the globe...
a number of trends were enacted between the U.S. and the USSR as they both endeavored in a tit-for-tat approach to disallow the other power from acquiring nuclear supremacy. This took form in a number of ways, both technologically and politically, and had massive political and cultural effects during the Cold War
Cold War
The Cold War was the continuing state from roughly 1946 to 1991 of political conflict, military tension, proxy wars, and economic competition between the Communist World—primarily the Soviet Union and its satellite states and allies—and the powers of the Western world, primarily the United States...
.
The first atomic bombs dropped on Hiroshima and Nagasaki were large, custom-made devices, requiring highly trained personnel for their arming and deployment. They could be dropped only from the largest bomber planes—at the time the B-29 Superfortress
B-29 Superfortress
The B-29 Superfortress is a four-engine propeller-driven heavy bomber designed by Boeing that was flown primarily by the United States Air Forces in late-World War II and through the Korean War. The B-29 was one of the largest aircraft to see service during World War II...
—and each plane could only hold a single bomb in its hold.
The first hydrogen bombs were similarly massive and complicated. This ratio of one plane to one bomb was still fairly impressive in comparison with conventional, non-nuclear weapons, but against other nuclear-armed countries it was considered a grave danger. In the immediate postwar years, the U.S. expended much effort on making the bombs "G.I.-proof"—capable of being used and deployed by members of the U.S. Army, rather than Nobel Prize–winning scientists. In the 1950s, the U.S. undertook a nuclear testing
Nuclear testing
Nuclear weapons tests are experiments carried out to determine the effectiveness, yield and explosive capability of nuclear weapons. Throughout the twentieth century, most nations that have developed nuclear weapons have tested them...
program to improve the nuclear arsenal.
Starting in 1951, the Nevada Test Site
Nevada Test Site
The Nevada National Security Site , previously the Nevada Test Site , is a United States Department of Energy reservation located in southeastern Nye County, Nevada, about northwest of the city of Las Vegas...
(in the Nevada
Nevada
Nevada is a state in the western, mountain west, and southwestern regions of the United States. With an area of and a population of about 2.7 million, it is the 7th-largest and 35th-most populous state. Over two-thirds of Nevada's people live in the Las Vegas metropolitan area, which contains its...
desert) became the primary location for all U.S. nuclear testing (in the USSR, Semipalatinsk Test Site
Semipalatinsk Test Site
The Semipalatinsk Test Site was the primary testing venue for the Soviet Union's nuclear weapons. It is located on the steppe in northeast Kazakhstan , south of the valley of the Irtysh River...
in Kazakhstan
Kazakhstan
Kazakhstan , officially the Republic of Kazakhstan, is a transcontinental country in Central Asia and Eastern Europe. Ranked as the ninth largest country in the world, it is also the world's largest landlocked country; its territory of is greater than Western Europe...
served a similar role). Tests were divided into two primary categories: "weapons related" (verifying that a new weapon worked or looking at exactly how it worked) and "weapons effects" (looking at how weapons behaved under various conditions or how structures behaved when subjected to weapons).
In the beginning, almost all nuclear tests were either "atmospheric" (conducted above ground, in the atmosphere
Earth's atmosphere
The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention , and reducing temperature extremes between day and night...
) or "underwater" (such as some of the tests done in the Marshall Islands
Marshall Islands
The Republic of the Marshall Islands , , is a Micronesian nation of atolls and islands in the middle of the Pacific Ocean, just west of the International Date Line and just north of the Equator. As of July 2011 the population was 67,182...
). Testing was used as a sign of both national and technological strength, but also raised questions about the safety of the tests, which released nuclear fallout
Nuclear fallout
Fallout is the residual radioactive material propelled into the upper atmosphere following a nuclear blast, so called because it "falls out" of the sky after the explosion and shock wave have passed. It commonly refers to the radioactive dust and ash created when a nuclear weapon explodes...
into the atmosphere (most dramatically with the Castle Bravo
Castle Bravo
Castle Bravo was the code name given to the first U.S. test of a dry fuel thermonuclear hydrogen bomb device, detonated on March 1, 1954 at Bikini Atoll, Marshall Islands, as the first test of Operation Castle. Castle Bravo was the most powerful nuclear device ever detonated by the United States ,...
test in 1954, but in more limited amounts with almost all atmospheric nuclear testing).
Because testing was seen as a sign of technological development (the ability to design usable weapons without some form of testing was considered dubious), halts on testing were often called for as stand-ins for halts in the nuclear arms race
Nuclear arms race
The nuclear arms race was a competition for supremacy in nuclear warfare between the United States, the Soviet Union, and their respective allies during the Cold War...
itself, and many prominent scientists and statesmen lobbied for a ban on nuclear testing. In 1958, the U.S., USSR, and the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
(a new nuclear power) declared a temporary testing moratorium for both political and health reasons, but by 1961 the Soviet Union had broken the moratorium and both the USSR and the U.S. began testing with great frequency.
As a show of political strength, the Soviet Union tested the largest-ever nuclear weapon in October 1961, the massive Tsar Bomba
Tsar Bomba
Tsar Bomba is the nickname for the AN602 hydrogen bomb, the most powerful nuclear weapon ever detonated. It was also referred to as Kuz'kina Mat , in this usage meaning "something that has not been seen before"....
, which was tested in a reduced state with a yield of around 50 megatons
TNT equivalent
TNT equivalent is a method of quantifying the energy released in explosions. The ton of TNT is a unit of energy equal to 4.184 gigajoules, which is approximately the amount of energy released in the detonation of one ton of TNT...
—in its full state it was estimated to have been around 100 Mt. The weapon was largely impractical for actual military use, but was hot enough to induce third-degree burns at a distance of 62 mi (100 km) away. In its full, "dirty" design, it would have increased the amount of worldwide fallout since 1945 by 25%.
In 1963, all nuclear and many non-nuclear states signed the Limited Test Ban Treaty, pledging to refrain from testing nuclear weapons in the atmosphere, underwater, or in outer space. The treaty permitted underground tests.
Most tests were considerably more modest, and worked for direct technical purposes as well as their potential political overtones. Weapons improvements took on two primary forms. One was an increase in efficiency and power, and within only a few years fission bombs were developed that were many times more powerful than the ones created during World War II. The other was a program of miniaturization, reducing the size of the nuclear weapons.
Smaller bombs meant that bombers could carry more of them, and also that they could be carried on the new generation of rocket
Rocket
A rocket is a missile, spacecraft, aircraft or other vehicle which obtains thrust from a rocket engine. In all rockets, the exhaust is formed entirely from propellants carried within the rocket before use. Rocket engines work by action and reaction...
s in development in the 1950s and 1960s. U.S. rocket science received a large boost in the postwar years, largely with the help of engineers acquired from the Nazi rocketry program. These included scientists such as Wernher von Braun
Wernher von Braun
Wernher Magnus Maximilian, Freiherr von Braun was a German rocket scientist, aerospace engineer, space architect, and one of the leading figures in the development of rocket technology in Nazi Germany during World War II and in the United States after that.A former member of the Nazi party,...
, who had helped design the V-2 rocket
V-2 rocket
The V-2 rocket , technical name Aggregat-4 , was a ballistic missile that was developed at the beginning of the Second World War in Germany, specifically targeted at London and later Antwerp. The liquid-propellant rocket was the world's first long-range combat-ballistic missile and first known...
s the Nazis launched across the English Channel
English Channel
The English Channel , often referred to simply as the Channel, is an arm of the Atlantic Ocean that separates southern England from northern France, and joins the North Sea to the Atlantic. It is about long and varies in width from at its widest to in the Strait of Dover...
. An American program, Project Paperclip, had endeavored to move German scientists into American hands (and away from Soviet hands) and put them to work for the U.S.
Weapons improvement
Early nuclear-tipped rockets—such as the MGR-1 Honest JohnMGR-1 Honest John
The MGR-1 Honest John rocket was the first nuclear-capable surface-to-surface rocket in the US arsenal.The first nuclear-authorized guided missile was the MGM-5 Corporal. Designated Artillery Rocket XM31, the first such rocket was tested 29 June 1951 and the first production rounds were delivered...
, first deployed by the U.S. in 1953—were surface-to-surface missiles with relatively short ranges (around 15 mi/25 km maximum) and yields around twice the size of the first fission weapons. The limited range meant they could only be used in certain types of military situations. U.S. rockets could not, for example, threaten Moscow
Moscow
Moscow is the capital, the most populous city, and the most populous federal subject of Russia. The city is a major political, economic, cultural, scientific, religious, financial, educational, and transportation centre of Russia and the continent...
with an immediate strike, and could only be used as "tactical" weapons (that is, for small-scale military situations).
Strategic Air Command
The Strategic Air Command was both a Major Command of the United States Air Force and a "specified command" of the United States Department of Defense. SAC was the operational establishment in charge of America's land-based strategic bomber aircraft and land-based intercontinental ballistic...
—a system of bomber
Bomber
A bomber is a military aircraft designed to attack ground and sea targets, by dropping bombs on them, or – in recent years – by launching cruise missiles at them.-Classifications of bombers:...
s headed by General Curtis LeMay
Curtis LeMay
Curtis Emerson LeMay was a general in the United States Air Force and the vice presidential running mate of American Independent Party candidate George Wallace in 1968....
(who previously presided over the firebombing of Japan
Bombing of Tokyo in World War II
The bombing of Tokyo, often referred to as a "firebombing", was conducted by the United States Army Air Forces during the Pacific campaigns of World War II. The U.S. mounted a small-scale raid on Tokyo in April 1942, with large morale effects...
during WWII). In operations like Chrome Dome
Operation Chrome Dome
Operation Chrome Dome was one of several United States Air Force Cold-War era airborne global alert duties or programs in which B-52 Stratofortress strategic bomber aircraft armed with thermonuclear weapons were assigned targets in the Soviet Union on schedules guaranteeing that a substantial...
, SAC kept nuclear-armed planes in the air 24 hours a day, ready for an order to attack Moscow.
These technological possibilities enabled nuclear strategy
Nuclear strategy
Nuclear strategy involves the development of doctrines and strategies for the production and use of nuclear weapons.As a sub-branch of military strategy, nuclear strategy attempts to match nuclear weapons as means to political ends...
to develop a logic considerably different than previous military thinking allowed. Because the threat of nuclear warfare
Nuclear warfare
Nuclear warfare, or atomic warfare, is a military conflict or political strategy in which nuclear weaponry is detonated on an opponent. Compared to conventional warfare, nuclear warfare can be vastly more destructive in range and extent of damage...
was so awful, it was first thought that it might make any war of the future impossible. President Dwight D. Eisenhower
Dwight D. Eisenhower
Dwight David "Ike" Eisenhower was the 34th President of the United States, from 1953 until 1961. He was a five-star general in the United States Army...
's doctrine of "massive retaliation" in the early years of the Cold War was a message to the USSR, saying that if the Red Army
Red Army
The Workers' and Peasants' Red Army started out as the Soviet Union's revolutionary communist combat groups during the Russian Civil War of 1918-1922. It grew into the national army of the Soviet Union. By the 1930s the Red Army was among the largest armies in history.The "Red Army" name refers to...
attempted to invade the parts of Europe not given to the Eastern bloc
Eastern bloc
The term Eastern Bloc or Communist Bloc refers to the former communist states of Eastern and Central Europe, generally the Soviet Union and the countries of the Warsaw Pact...
during the Potsdam Conference (such as West Germany
West Germany
West Germany is the common English, but not official, name for the Federal Republic of Germany or FRG in the period between its creation in May 1949 to German reunification on 3 October 1990....
), nuclear weapons would be used against the Soviet troops and potentially the Soviet leaders.
With the development of more rapid-response technologies (such as rockets and long-range bombers), this policy began to shift. If the Soviet Union also had nuclear weapons and a policy of "massive retaliation" was carried out, it was reasoned, then any Soviet forces not killed in the initial attack, or launched while the attack was ongoing, would be able to serve their own form of nuclear "retaliation" against the U.S. Recognizing that this was an undesirable outcome, military officers and game theorists
Game theory
Game theory is a mathematical method for analyzing calculated circumstances, such as in games, where a person’s success is based upon the choices of others...
at the RAND
RAND
RAND Corporation is a nonprofit global policy think tank first formed to offer research and analysis to the United States armed forces by Douglas Aircraft Company. It is currently financed by the U.S. government and private endowment, corporations including the healthcare industry, universities...
think tank
Think tank
A think tank is an organization that conducts research and engages in advocacy in areas such as social policy, political strategy, economics, military, and technology issues. Most think tanks are non-profit organizations, which some countries such as the United States and Canada provide with tax...
developed a nuclear warfare strategy that was eventually called Mutually Assured Destruction (MAD).
First strike
In nuclear strategy, a first strike is a preemptive surprise attack employing overwhelming force. First strike capability is a country's ability to defeat another nuclear power by destroying its arsenal to the point where the attacking country can survive the weakened retaliation while the opposing...
and second strike
Second strike
In nuclear strategy, a second strike capability is a country's assured ability to respond to a nuclear attack with powerful nuclear retaliation against the attacker...
. First strike meant the first use of nuclear weapons by one nuclear-equipped nation against another nuclear-equipped nation. If the attacking nation did not prevent the attacked nation from a nuclear response, the attacked nation would respond with a second strike against the attacking nation. In this situation, whether the U.S. first attacked the USSR or the USSR first attacked the U.S., the end result would be that both nations would be damaged to the point of utter social collapse.
According to game theory, because starting a nuclear war was suicidal, no logical country would "shoot first." However, if a country could launch a first strike that utterly destroyed the target country's ability to respond, that might give that country the confidence to initiate a nuclear war. The object of a country operating by the MAD doctrine is to deny the opposing country this first strike capability.
MAD played on two seemingly opposed modes of thought: cold logic and emotional fear. The English phrase MAD was often known by , "nuclear deterrence," was translated by the French as "dissuasion," and "terrorization" by the Russians. This apparent paradox of nuclear war was summed up by British Prime Minister Winston Churchill
Winston Churchill
Sir Winston Leonard Spencer-Churchill, was a predominantly Conservative British politician and statesman known for his leadership of the United Kingdom during the Second World War. He is widely regarded as one of the greatest wartime leaders of the century and served as Prime Minister twice...
as "the worse things get, the better they are"—the greater the threat of mutual destruction, the safer the world would be.
This philosophy made a number of technological and political demands on participating nations. For one thing, it said that it should always be assumed that an enemy nation may be trying to acquire first strike capability, which must always be avoided. In American politics this translated into demands to avoid "bomber gap
Bomber gap
The "bomber gap" was the unfounded belief in the Cold War-era United States that the Soviet Union had gained an advantage in deploying jet-powered strategic bombers. Widely accepted for several years, the gap was used as a political talking point in order to justify greatly increased defense spending...
s" and "missile gap
Missile gap
The missile gap was the term used in the United States for the perceived disparity between the number and power of the weapons in the U.S.S.R. and U.S. ballistic missile arsenals during the Cold War. The gap only existed in exaggerated estimates made by the Gaither Committee in 1957 and United...
s" where the Soviet Union could potentially "out shoot" the Americans. It also encouraged the production of thousands of nuclear weapons by both the U.S. and the USSR, far more than needed to simply destroy the major civilian and military infrastructures of the opposing country.
These policies and strategies were satirized in the 1964 Stanley Kubrick
Stanley Kubrick
Stanley Kubrick was an American film director, writer, producer, and photographer who lived in England during most of the last four decades of his career...
film Dr. Strangelove, in which the Soviets, unable to keep up with the US's first strike capability, instead plan for MAD by building a Doomsday Machine
Doomsday device
A doomsday device is a hypothetical construction — usually a weapon, or collection of weapons — which could destroy all life on a planet, particularly the Earth, or destroy the planet itself, bringing "doomsday", a term used for the end of planet Earth...
, and thus, after a (literally) mad US General orders a nuclear attack on the USSR, the end of the world is brought about.
Command and Control (military)
Command and control, or C2, in a military organization can be defined as the exercise of authority and direction by a properly designated commanding officer over assigned and attached forces in the accomplishment of the mission...
systems could not adequately react to a nuclear attack, so great lengths were taken to develop computer
Computer
A computer is a programmable machine designed to sequentially and automatically carry out a sequence of arithmetic or logical operations. The particular sequence of operations can be changed readily, allowing the computer to solve more than one kind of problem...
s that could look for enemy attacks and direct rapid responses.
The U.S., poured massive funding into development of SAGE
Semi Automatic Ground Environment
The Semi-Automatic Ground Environment was an automated control system for tracking and intercepting enemy bomber aircraft used by NORAD from the late 1950s into the 1980s...
, a system that could track and intercept enemy bomber aircraft using information from remote radar
Radar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
stations. It was the first computer system to feature real-time
Real-time computing
In computer science, real-time computing , or reactive computing, is the study of hardware and software systems that are subject to a "real-time constraint"— e.g. operational deadlines from event to system response. Real-time programs must guarantee response within strict time constraints...
processing, multiplexing
Multiplexing
The multiplexed signal is transmitted over a communication channel, which may be a physical transmission medium. The multiplexing divides the capacity of the low-level communication channel into several higher-level logical channels, one for each message signal or data stream to be transferred...
, and display device
Display device
A display device is an output device for presentation of information in visual or tactile form...
s. It was the first "general" computing machine, and a direct predecessor of modern computers.
Anti-nuclear
Bombers and short-range rockets were not reliable: planes could be shot down, and earlier nuclear missiles could cover only a limited range— for example, the first Soviet rockets' range limited them to targets in Europe. However, by the 1960s1960s
The 1960s was the decade that started on January 1, 1960, and ended on December 31, 1969. It was the seventh decade of the 20th century.The 1960s term also refers to an era more often called The Sixties, denoting the complex of inter-related cultural and political trends across the globe...
, both the United States and the Soviet Union had developed intercontinental ballistic missile
Intercontinental ballistic missile
An intercontinental ballistic missile is a ballistic missile with a long range typically designed for nuclear weapons delivery...
s, which could be launched from extremely remote areas far away from their target. They had also developed submarine-launched ballistic missile
Submarine-launched ballistic missile
A submarine-launched ballistic missile is a ballistic missile capable of delivering a nuclear warhead that can be launched from submarines. Modern variants usually deliver multiple independently targetable reentry vehicles each of which carries a warhead and allows a single launched missile to...
s, which had less range but could be launched from submarines very close to the target without any radar warning. This made any national protection from nuclear missiles increasingly impractical.
The military realities made for a precarious diplomatic situation. The international politics of brinkmanship
Brinkmanship
Brinkmanship is the practice of pushing dangerous events to the verge of disaster in order to achieve the most advantageous outcome...
led leaders to exclaim their willingness to participate in a nuclear war rather than concede any advantage to their opponents, feeding public fears that their generation may be the last. Civil defense
Civil defense
Civil defense, civil defence or civil protection is an effort to protect the citizens of a state from military attack. It uses the principles of emergency operations: prevention, mitigation, preparation, response, or emergency evacuation, and recovery...
programs undertaken by both superpowers, exemplified by the construction of fallout shelters and urging civilians about the "survivability" of nuclear war, did little to ease public concerns.
Lockheed U-2
The Lockheed U-2, nicknamed "Dragon Lady", is a single-engine, very high-altitude reconnaissance aircraft operated by the United States Air Force and previously flown by the Central Intelligence Agency . It provides day and night, very high-altitude , all-weather intelligence gathering...
spy plane photographed a series of launch sites for medium-range ballistic missiles being constructed on the island of Cuba
Cuba
The Republic of Cuba is an island nation in the Caribbean. The nation of Cuba consists of the main island of Cuba, the Isla de la Juventud, and several archipelagos. Havana is the largest city in Cuba and the country's capital. Santiago de Cuba is the second largest city...
, just off the coast of the southern United States, beginning what became known as the Cuban Missile Crisis
Cuban Missile Crisis
The Cuban Missile Crisis was a confrontation among the Soviet Union, Cuba and the United States in October 1962, during the Cold War...
. The U.S. administration of John F. Kennedy
John F. Kennedy
John Fitzgerald "Jack" Kennedy , often referred to by his initials JFK, was the 35th President of the United States, serving from 1961 until his assassination in 1963....
concluded that the Soviet Union, then led by Nikita Khrushchev
Nikita Khrushchev
Nikita Sergeyevich Khrushchev led the Soviet Union during part of the Cold War. He served as First Secretary of the Communist Party of the Soviet Union from 1953 to 1964, and as Chairman of the Council of Ministers, or Premier, from 1958 to 1964...
, was planning to station Russian nuclear missiles on the island, which was under the control of Communist Fidel Castro
Fidel Castro
Fidel Alejandro Castro Ruz is a Cuban revolutionary and politician, having held the position of Prime Minister of Cuba from 1959 to 1976, and then President from 1976 to 2008. He also served as the First Secretary of the Communist Party of Cuba from the party's foundation in 1961 until 2011...
. On October 22, Kennedy announced the discoveries in a televised address. He announced a naval blockade
Blockade
A blockade is an effort to cut off food, supplies, war material or communications from a particular area by force, either in part or totally. A blockade should not be confused with an embargo or sanctions, which are legal barriers to trade, and is distinct from a siege in that a blockade is usually...
around Cuba that would turn back Soviet nuclear shipments, and warned that the military was prepared "for any eventualities." The missiles had 2,400 mile (4,000 km) range, and would allow the Soviet Union to quickly destroy many major American cities on the Eastern Seaboard
Eastern seaboard
An Eastern seaboard can mean any easternmost part of a continent, or its countries, states and/or cities.Eastern seaboard may also refer to:* East Coast of Australia* East Coast of the United States* Eastern Seaboard of Thailand-See also:...
if a nuclear war began.
The leaders of the two superpowers stood nose to nose, seemingly poised over the beginnings of a third world war
World War III
World War III denotes a successor to World War II that would be on a global scale, with common speculation that it would be likely nuclear and devastating in nature....
. Khrushchev's ambitions for putting the weapons on the island were motivated in part by the fact that the U.S. had stationed similar weapons in Britain
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
, Italy
Italy
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...
, and nearby Turkey
Turkey
Turkey , known officially as the Republic of Turkey , is a Eurasian country located in Western Asia and in East Thrace in Southeastern Europe...
, and had previously attempted to sponsor an invasion of Cuba the year before in the failed Bay of Pigs Invasion
Bay of Pigs Invasion
The Bay of Pigs Invasion was an unsuccessful action by a CIA-trained force of Cuban exiles to invade southern Cuba, with support and encouragement from the US government, in an attempt to overthrow the Cuban government of Fidel Castro. The invasion was launched in April 1961, less than three months...
. On October 26, Khrushchev sent a message to Kennedy offering to withdraw all missiles if Kennedy committed to a policy of no future invasions of Cuba. Khrushchev worded the threat of assured destruction eloquently:
"You and I should not now pull on the ends of the rope in which you have tied a knot of war, because the harder you and I pull, the tighter the knot will become. And a time may come when this knot is tied so tight that the person who tied it is no longer capable of untying it, and then the knot will have to be cut. What that would mean I need not explain to you, because you yourself understand perfectly what dreaded forces our two countries possess."
A day later, however, the Russians sent another message, this time demanding that the U.S. remove its missiles from Turkey before any missiles were withdrawn from Cuba. On the same day, a U-2 plane was shot down over Cuba and another almost intercepted over Russia, as Soviet merchant ships neared the quarantine zone. Kennedy responded by accepting the first deal publicly, and sending his brother Robert to the Soviet embassy to accept the second deal privately.
On October 28, the Soviet ships stopped at the quarantine line and, after some hesitation, turned back towards the Soviet Union. Khrushchev announced that he had ordered the removal of all missiles in Cuba, and U.S. Secretary of State Dean Rusk
Dean Rusk
David Dean Rusk was the United States Secretary of State from 1961 to 1969 under presidents John F. Kennedy and Lyndon B. Johnson. Rusk is the second-longest serving U.S...
was moved to comment, "We went eyeball to eyeball, and the other fellow just blinked."
The Crisis was later seen as the closest the U.S. and the USSR ever came to nuclear war and had been narrowly averted by last-minute compromise by both superpowers. Fears of communication difficulties led to the installment of the first hotline
Hotline
In telecommunication, a hotline is a point-to-point communications link in which a call is automatically directed to the preselected destination without any additional action by the user when the end instrument goes off-hook...
, a direct link between the superpowers that allowed them to more easily discuss future military activities and political maneuverings. It had been made clear that missiles, bombers, submarines, and computerized firing systems made escalating any situation to Armageddon far more easy than anybody desired.
After stepping so close to the brink, both the U.S. and the USSR worked to reduce their nuclear tensions in the years immediately following. The most immediate culmination of this work was the signing of the Partial Test Ban Treaty
Partial Test Ban Treaty
The treaty banning nuclear weapon tests in the atmosphere, in outer space and under water, often abbreviated as the Partial Test Ban Treaty , Limited Test Ban Treaty , or Nuclear Test Ban Treaty is a treaty prohibiting all test detonations of nuclear weapons...
in 1963, in which the U.S. and USSR agreed to no longer test nuclear weapons in the atmosphere, underwater, or in outer space. Testing underground continued, allowing for further weapons development, but the worldwide fallout risks were purposefully reduced, and the era of using massive nuclear tests as a form of saber-rattling ended.
In December 1979, NATO decided to deploy cruise and Pershing II missiles in Western Europe in response to Soviet deployment of intermediate range mobile missiles, and in the early 1980s, a "dangerous Soviet-US nuclear confrontation" arose. In New York on June 12, 1982, one million people gathered to protest nuclear weapons, and to support the second UN Special Session on Disarmament. As the nuclear abolitionist movement grew, there were many protests at the Nevada Test Site
Nevada Test Site
The Nevada National Security Site , previously the Nevada Test Site , is a United States Department of Energy reservation located in southeastern Nye County, Nevada, about northwest of the city of Las Vegas...
. For example, on February 6, 1987, nearly 2,000 demonstrators, including six members of Congress, protested against nuclear weapons testing and more than 400 people were arrested. Four of the significant groups organizing this renewal of anti-nuclear activism
Anti-nuclear movement in the United States
The anti-nuclear movement in the United States consists of more than 80 anti-nuclear groups which have acted to oppose nuclear power or nuclear weapons, or both, in the United States. These groups include the Abalone Alliance, Clamshell Alliance, Institute for Energy and Environmental Research,...
were Greenpeace
Greenpeace
Greenpeace is a non-governmental environmental organization with offices in over forty countries and with an international coordinating body in Amsterdam, The Netherlands...
, The American Peace Test, The Western Shoshone, and Nevada Desert Experience
Nevada Desert Experience
The Nevada Desert Experience is a name for the movement to stop U.S. nuclear weapons testing that came into use in the middle 1980s. It is also the name of a particular anti-nuclear organization which continues to create public events to question the morality and intelligence of the U.S. nuclear...
.
Initial proliferation
In the fifties and sixties, three more countries joined the "nuclear club."The United Kingdom had been an integral part of the Manhattan Project
Manhattan Project
The Manhattan Project was a research and development program, led by the United States with participation from the United Kingdom and Canada, that produced the first atomic bomb during World War II. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the US Army...
following the Quebec Agreement
Quebec Agreement
The Quebec Agreement is an Anglo-Canadian-American document outlining the terms of nuclear nonproliferation between the United Kingdom and the United States, and signed by Winston Churchill and Franklin Delano Roosevelt on August 19, 1943, two years before the end of World War II, in Quebec City,...
in 1943. The passing of the McMahon Act by the United States in 1946 unilaterally broke this partnership and prevented the passage of any further information to the United Kingdom. The British Government, under Clement Attlee
Clement Attlee
Clement Richard Attlee, 1st Earl Attlee, KG, OM, CH, PC, FRS was a British Labour politician who served as the Prime Minister of the United Kingdom from 1945 to 1951, and as the Leader of the Labour Party from 1935 to 1955...
, determined that a British Bomb was essential. Because of British involvement in the Manhattan Project, Britain had extensive knowledge in some areas, but not in others.
An improved version of 'Fat Man' was developed, and on 26 February 1952, Prime Minister Winston Churchill
Winston Churchill
Sir Winston Leonard Spencer-Churchill, was a predominantly Conservative British politician and statesman known for his leadership of the United Kingdom during the Second World War. He is widely regarded as one of the greatest wartime leaders of the century and served as Prime Minister twice...
announced that the United Kingdom also had an atomic bomb and a successful test
Operation Hurricane
Operation Hurricane was the test of the first British atomic device on 3 October 1952. A plutonium implosion device was detonated in the lagoon between the Montebello Islands, Western Australia....
took place on the 3rd October 1952. At first these were free-fall bombs, intended for use by the V Force
V bomber
The term V bomber was used for the Royal Air Force aircraft during the 1950s and 1960s that comprised the United Kingdom's strategic nuclear strike force known officially as the V-force or Bomber Command Main Force...
of jet bombers. A Vickers Valiant
Vickers Valiant
The Vickers-Armstrongs Valiant was a British four-jet bomber, once part of the Royal Air Force's V bomber nuclear force in the 1950s and 1960s...
dropped the first UK nuclear weapon on 11 October 1956 at Maralinga, South Australia
South Australia
South Australia is a state of Australia in the southern central part of the country. It covers some of the most arid parts of the continent; with a total land area of , it is the fourth largest of Australia's six states and two territories.South Australia shares borders with all of the mainland...
. Later came a missile, Blue Steel
Blue Steel missile
The Avro Blue Steel was a British air-launched, rocket-propelled nuclear stand-off missile, built to arm the V bomber force. It was the primary British nuclear deterrent weapon until the Royal Navy started operating Polaris missile armed nuclear submarines....
, intended for carriage by the V Force bombers, and then the Blue Streak
Blue Streak missile
The Blue Streak missile was a British medium range ballistic missile . The Operational Requirement for the missile was issued in 1955 and the design was complete by 1957...
medium-range ballistic missile
Medium-range ballistic missile
A medium-range ballistic missile , is a type of ballistic missile with medium range, this last classification depending on the standards of certain organizations. Within the U.S. Department of Defense, a medium range missile is defined by having a maximum range of between 1,000 and 3,000 km1...
(later canceled). Anglo-American cooperation on Nuclear weapons was restored by the 1958 US-UK Mutual Defence Agreement
1958 US-UK Mutual Defence Agreement
The 1958 US–UK Mutual Defence Agreement is a bilateral treaty between the United States and the United Kingdom on nuclear weapons cooperation.It was signed after the UK successfully tested its first hydrogen bomb during Operation Grapple. While the U.S...
. As a result of this and the Polaris Sales Agreement
Polaris Sales Agreement
The Polaris Sales Agreement was an agreement between the United States and the United Kingdom which formally arranged for the Polaris missile system to be provided to the UK to maintain its independent nuclear deterrent. The arrangement had been set up in principle as a result of the Nassau Agreement...
, the United Kingdom has bought United States designs for submarine missiles and fitted its own warheads. It retains full independent control over the use of the missiles. It no longer possesses any free-fall bombs.
France had been heavily involved in nuclear research before World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
through the work of the Joliot-Curie
Joliot-Curie
Joliot-Curie may refer to more than one person:* Frédéric Joliot-Curie- a French physicist and Nobel prize-winner* Irène Joliot-Curie - his wife and joint prize-winner with her husband...
s. This was discontinued after the war because of the instability of the Fourth Republic
French Fourth Republic
The French Fourth Republic was the republican government of France between 1946 and 1958, governed by the fourth republican constitution. It was in many ways a revival of the Third Republic, which was in place before World War II, and suffered many of the same problems...
and lack of finances. However, in the 1950s, France launched a civil nuclear research program, which produced plutonium as a byproduct.
In 1956, France formed a secret Committee for the Military Applications of Atomic Energy and a development program for delivery vehicles. With the return of Charles de Gaulle
Charles de Gaulle
Charles André Joseph Marie de Gaulle was a French general and statesman who led the Free French Forces during World War II. He later founded the French Fifth Republic in 1958 and served as its first President from 1959 to 1969....
to the French presidency in 1958, final decisions to build a bomb were made, which led to a successful test in 1960. Since then, France has developed and maintained its own nuclear deterrent
Force de frappe
The Force de Frappe is the designation of what used to be a triad of air-, sea- and land-based nuclear weapons intended for dissuasion, and consequential deterrence...
.
In 1951, China and the Soviet Union signed an agreement whereby China supplied uranium ore in exchange for technical assistance in producing nuclear weapons. In 1953, China established a research program under the guise of civilian nuclear energy. Throughout the 1950s the Soviet Union provided large amounts of equipment. But as the relations between the two countries worsened the Soviets reduced the amount of assistance and, in 1959, refused to donate a bomb for copying purposes. Despite this, the Chinese made rapid progress and tested an atomic bomb on the October 16, 1964 at Lop Nur
Lop Nur
Lop Lake or Lop Nur is a group of small, now seasonal salt lake sand marshes between the Taklamakan and Kuruktag deserts in the Bayingolin Mongol Autonomous Prefecture, southeastern portion of Xinjiang Uygur Autonomous Region in the People's Republic of China.The lake system into which the Tarim...
. They tested a nuclear missile on October 25, 1966, and a hydrogen bomb on June 14, 1967.
Chinese nuclear warheads were produced from 1968 and thermonuclear warheads from 1974. It is also thought that Chinese warheads have been successfully miniaturised from 2200 kg to 700 kg through the use of designs obtained by espionage
Espionage
Espionage or spying involves an individual obtaining information that is considered secret or confidential without the permission of the holder of the information. Espionage is inherently clandestine, lest the legitimate holder of the information change plans or take other countermeasures once it...
from the United States. The current number of weapons is unknown owing to strict secrecy, but it is thought that up to 2000 warheads may have been produced, though far fewer may be available for use. China is the only nuclear weapons state to have guaranteed the non-first use of nuclear weapons.
Cold War
Balance of power in international relations
In international relations, a balance of power exists when there is parity or stability between competing forces. The concept describes a state of affairs in the international system and explains the behavior of states in that system...
between the Eastern and Western blocs and the fear of global destruction prevented the further military use of atomic bombs. This fear was even a central part of Cold War
Cold War
The Cold War was the continuing state from roughly 1946 to 1991 of political conflict, military tension, proxy wars, and economic competition between the Communist World—primarily the Soviet Union and its satellite states and allies—and the powers of the Western world, primarily the United States...
strategy, referred to as the doctrine of Mutually Assured Destruction ("MAD" for short). So important was this balance to international political stability that a treaty, the Anti-Ballistic Missile Treaty
Anti-Ballistic Missile Treaty
The Anti-Ballistic Missile Treaty was a treaty between the United States and the Soviet Union on the limitation of the anti-ballistic missile systems used in defending areas against missile-delivered nuclear weapons....
(or ABM treaty), was signed by the U.S. and the USSR
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
in 1972 to curtail the development of defenses against nuclear weapons and the ballistic missile
Ballistic missile
A ballistic missile is a missile that follows a sub-orbital ballistic flightpath with the objective of delivering one or more warheads to a predetermined target. The missile is only guided during the relatively brief initial powered phase of flight and its course is subsequently governed by the...
s that carry them. This doctrine resulted in a large increase in the number of nuclear weapons, as each side sought to ensure it possessed the firepower to destroy the opposition in all possible scenarios and against all perceived threats.
Early delivery systems for nuclear devices were primarily bombers like the United States B-29 Superfortress
B-29 Superfortress
The B-29 Superfortress is a four-engine propeller-driven heavy bomber designed by Boeing that was flown primarily by the United States Air Forces in late-World War II and through the Korean War. The B-29 was one of the largest aircraft to see service during World War II...
and Convair B-36
Convair B-36
The Convair B-36 "Peacemaker" was a strategic bomber built by Convair and operated solely by the United States Air Force from 1949 to 1959. The B-36 was the largest mass-produced piston engine aircraft ever made. It had the longest wingspan of any combat aircraft ever built , although there have...
, and later the B-52 Stratofortress
B-52 Stratofortress
The Boeing B-52 Stratofortress is a long-range, subsonic, jet-powered strategic bomber operated by the United States Air Force since the 1950s. The B-52 was designed and built by Boeing, who have continued to provide maintainence and upgrades to the aircraft in service...
. Ballistic missile systems, based on Wernher von Braun
Wernher von Braun
Wernher Magnus Maximilian, Freiherr von Braun was a German rocket scientist, aerospace engineer, space architect, and one of the leading figures in the development of rocket technology in Nazi Germany during World War II and in the United States after that.A former member of the Nazi party,...
's World War II designs (specifically the V2 rocket), were developed by both United States and Soviet Union teams (in the case of the U.S., effort was directed by the German scientists and engineers although the Soviet Union also made extensive use of captured German scientists, engineers, and technical data).
These systems were used to launch satellites, such as Sputnik, and to propel the Space Race
Space Race
The Space Race was a mid-to-late 20th century competition between the Soviet Union and the United States for supremacy in space exploration. Between 1957 and 1975, Cold War rivalry between the two nations focused on attaining firsts in space exploration, which were seen as necessary for national...
, but they were primarily developed to create Intercontinental Ballistic Missiles (ICBMs) that could deliver nuclear weapons anywhere on the globe. Development of these systems continued throughout the Cold War
Cold War
The Cold War was the continuing state from roughly 1946 to 1991 of political conflict, military tension, proxy wars, and economic competition between the Communist World—primarily the Soviet Union and its satellite states and allies—and the powers of the Western world, primarily the United States...
—though plans and treaties, beginning with the Strategic Arms Limitation Treaty (SALT I), restricted deployment of these systems until, after the fall of the Soviet Union, system development essentially halted, and many weapons were disabled and destroyed (see nuclear disarmament
Nuclear disarmament
Nuclear disarmament refers to both the act of reducing or eliminating nuclear weapons and to the end state of a nuclear-free world, in which nuclear weapons are completely eliminated....
).
There have been a number of potential nuclear disasters. Following air accidents U.S. nuclear weapons have been lost near Atlantic City, New Jersey
Atlantic City, New Jersey
Atlantic City is a city in Atlantic County, New Jersey, United States, and a nationally renowned resort city for gambling, shopping and fine dining. The city also served as the inspiration for the American version of the board game Monopoly. Atlantic City is located on Absecon Island on the coast...
(1957); Savannah, Georgia
Savannah, Georgia
Savannah is the largest city and the county seat of Chatham County, in the U.S. state of Georgia. Established in 1733, the city of Savannah was the colonial capital of the Province of Georgia and later the first state capital of Georgia. Today Savannah is an industrial center and an important...
(1958) (see Tybee Bomb
Tybee Bomb
The Tybee Island B-47 crash was an incident on February 5, 1958, in which the United States Air Force lost a Mark 15 hydrogen bomb in the waters off Tybee Island near Savannah, Georgia, USA. During a practice exercise the B-47 bomber carrying it collided in midair with an F-86 fighter plane. To...
); Goldsboro, North Carolina
Goldsboro, North Carolina
Goldsboro is a city in Wayne County, North Carolina, United States. The population was 37,597 at the 2008 census estimate. It is the principal city of and is included in the Goldsboro, North Carolina Metropolitan Statistical Area. The nearby town of Waynesboro was founded in 1787 and Goldsboro was...
(1961); off the coast of Okinawa (1965); in the sea near Palomares
Palomares, Almería
Palomares is an agricultural, fishing and tourist village on the Mediterranean Sea in the Almería province of Andalusia, Spain. It is about 20 meters above sea level...
, Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
(1966) (see 1966 Palomares B-52 crash); and near Thule, Greenland (1968) (see 1968 Thule Air Base B-52 crash). Most of the lost weapons were recovered, the Spanish device after three months' effort by the DSV Alvin
DSV Alvin
Alvin is a manned deep-ocean research submersible owned by the United States Navy and operated by the Woods Hole Oceanographic Institution in Woods Hole, Massachusetts. The vehicle was built by General Mills' Electronics Group in the same factory used to manufacture breakfast cereal-producing...
and DSV Aluminaut
Aluminaut
Aluminaut was built in 1964 and was the world's first aluminum submarine. The 80-ton, 51 foot manned deep-ocean research submersible was built by Reynolds Metals Company, which was seeking to advertise the utility of aluminum...
.
The Soviet Union was less forthcoming about such incidents, but the environmental group Greenpeace
Greenpeace
Greenpeace is a non-governmental environmental organization with offices in over forty countries and with an international coordinating body in Amsterdam, The Netherlands...
believes that there are around forty non-U.S. nuclear devices that have been lost and not recovered, compared to eleven lost by America, mostly in submarine disasters. The U.S. has tried to recover Soviet devices, notably in the 1974 Operation Jennifer using the specialist salvage vessel Hughes Glomar Explorer.
On January 27, 1967, more than 60 nations signed the Outer Space Treaty
Outer Space Treaty
The Outer Space Treaty, formally the Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies, is a treaty that forms the basis of international space law...
, banning nuclear weapons in space.
The end of the Cold War
Cold War
The Cold War was the continuing state from roughly 1946 to 1991 of political conflict, military tension, proxy wars, and economic competition between the Communist World—primarily the Soviet Union and its satellite states and allies—and the powers of the Western world, primarily the United States...
failed to end the threat of nuclear weapon use, although global fears of nuclear war
Nuclear warfare
Nuclear warfare, or atomic warfare, is a military conflict or political strategy in which nuclear weaponry is detonated on an opponent. Compared to conventional warfare, nuclear warfare can be vastly more destructive in range and extent of damage...
reduced substantially.
In a major move of symbolic de-escalation, Boris Yeltsin
Boris Yeltsin
Boris Nikolayevich Yeltsin was the first President of the Russian Federation, serving from 1991 to 1999.Originally a supporter of Mikhail Gorbachev, Yeltsin emerged under the perestroika reforms as one of Gorbachev's most powerful political opponents. On 29 May 1990 he was elected the chairman of...
, on January 26, 1992, announced that Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
planned to stop targeting United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
cities with nuclear weapons.
Second nuclear age
Although it had started before the end of the Cold WarCold War
The Cold War was the continuing state from roughly 1946 to 1991 of political conflict, military tension, proxy wars, and economic competition between the Communist World—primarily the Soviet Union and its satellite states and allies—and the powers of the Western world, primarily the United States...
, the second nuclear age—proliferation of nuclear weapons
Nuclear proliferation
Nuclear proliferation is a term now used to describe the spread of nuclear weapons, fissile material, and weapons-applicable nuclear technology and information, to nations which are not recognized as "Nuclear Weapon States" by the Treaty on the Nonproliferation of Nuclear Weapons, also known as the...
among lesser powers and for reasons other than the American-Soviet rivalry—really began with the end of the Cold War.
After the collapse of Eastern Military High Command
Evolution of Pakistan Eastern Command plan
The Eastern Military High Command of the Pakistan Armed Forces was a field-level military command headed by an appointed senior 3-star officer, who was designated the Unified Commander of the Eastern Military High Command...
and the disintegration
Bangladesh Liberation War
The Bangladesh Liberation War was an armed conflict pitting East Pakistan and India against West Pakistan. The war resulted in the secession of East Pakistan, which became the independent nation of Bangladesh....
of Pakistan as a result of 1971 Winter war
Indo-Pakistani War of 1971
The Indo-Pakistani War of 1971 was a military conflict between India and Pakistan. Indian, Bangladeshi and international sources consider the beginning of the war to be Operation Chengiz Khan, Pakistan's December 3, 1971 pre-emptive strike on 11 Indian airbases...
, Bhutto
Zulfikar Ali Bhutto
Zulfikar Ali Bhutto was 9th Prime Minister of Pakistan from 1973 to 1977, and prior to that, 4th President of Pakistan from 1971 to 1973. Bhutto was the founder of the Pakistan Peoples Party — the largest and most influential political party in Pakistan— and served as its chairman until his...
of Pakistan launched and embarked the scientific research on nuclear weapons. This programme was delegated to Munir Ahmad Khan
Munir Ahmad Khan
Munir Ahmad Khan , HI, was a Pakistani nuclear engineer and a scientist who served as the Chairman of the Pakistan Atomic Energy Commission from 1972 to 1991...
, Abdul Qadeer Khan
Abdul Qadeer Khan
Abdul Qadeer Khan , also known in Pakistan as Mohsin-e-Pakistan , D.Eng, Sc.D, HI, NI , FPAS; more widely known as Dr. A. Q...
, and Salam
Abdus Salam
Mohammad Abdus Salam, NI, SPk Mohammad Abdus Salam, NI, SPk Mohammad Abdus Salam, NI, SPk (Urdu: محمد عبد السلام, pronounced , (January 29, 1926– November 21, 1996) was a Pakistani theoretical physicist and Nobel laureate in Physics for his work on the electroweak unification of the...
who later go on to win the Nobel Prize
Nobel Prize in Physics
The Nobel Prize in Physics is awarded once a year by the Royal Swedish Academy of Sciences. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895 and awarded since 1901; the others are the Nobel Prize in Chemistry, Nobel Prize in Literature, Nobel Peace Prize, and...
. India's first atomic-test explosion was in 1974 with Smiling Buddha
Smiling Buddha
The Smiling Buddha, formally designated as Pokhran-I, was the codename given to Republic of India's first nuclear test explosion that took place at the long-constructed Indian Army base, Pokhran Test Range at Pokhran municipality, Rajasthan state on 18 May 1974 at 8:05 a.m....
, which it described as a "peaceful nuclear explosion". The Indian test caused Pakistan to spurred its programme, and with Dr. A. Q. Khan, the ISI conduct successful espionage operations in the Netherlands, while also developing the programme ingeniously on the other side. India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
tested fission and perhaps fusion devices in 1998 (See Shakti), and Pakistan successfully tested fission devices that same year (See Chagai-I
Chagai-I
The Chagai-I was a codename referring to the five underground nuclear tests conducted by Pakistan at 15:15hrs in 28th May of 1998. It was named Chagai-I, as the tests were conducted in the Chagai District...
), raising concerns that they would use nuclear weapons on each other. All of the former Soviet bloc countries with nuclear weapons (Belarus
Belarus
Belarus , officially the Republic of Belarus, is a landlocked country in Eastern Europe, bordered clockwise by Russia to the northeast, Ukraine to the south, Poland to the west, and Lithuania and Latvia to the northwest. Its capital is Minsk; other major cities include Brest, Grodno , Gomel ,...
, Ukraine
Ukraine
Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...
, and Kazakhstan
Kazakhstan
Kazakhstan , officially the Republic of Kazakhstan, is a transcontinental country in Central Asia and Eastern Europe. Ranked as the ninth largest country in the world, it is also the world's largest landlocked country; its territory of is greater than Western Europe...
) returned their warheads to Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
by 1996.
In January 2004, metallurgist and top weapon scientist Abdul Qadeer Khan confessed to having been a part of an international proliferation
Nuclear proliferation
Nuclear proliferation is a term now used to describe the spread of nuclear weapons, fissile material, and weapons-applicable nuclear technology and information, to nations which are not recognized as "Nuclear Weapon States" by the Treaty on the Nonproliferation of Nuclear Weapons, also known as the...
network of materials, knowledge, and machines from Pakistan to Libya
Libya
Libya is an African country in the Maghreb region of North Africa bordered by the Mediterranean Sea to the north, Egypt to the east, Sudan to the southeast, Chad and Niger to the south, and Algeria and Tunisia to the west....
, Iran
Iran
Iran , officially the Islamic Republic of Iran , is a country in Southern and Western Asia. The name "Iran" has been in use natively since the Sassanian era and came into use internationally in 1935, before which the country was known to the Western world as Persia...
, and North Korea
North Korea
The Democratic People’s Republic of Korea , , is a country in East Asia, occupying the northern half of the Korean Peninsula. Its capital and largest city is Pyongyang. The Korean Demilitarized Zone serves as the buffer zone between North Korea and South Korea...
.
South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
also had an active program to develop uranium-based nuclear weapons, but dismantled its nuclear weapon program in the 1990s
1990s
File:1990s decade montage.png|From left, clockwise: The Hubble Space Telescope floats in space after it was taken up in 1990; American F-16s and F-15s fly over burning oil fields and the USA Lexie in Operation Desert Storm, also known as the 1991 Gulf War; The signing of the Oslo Accords on...
. Experts do not believe it actually tested such a weapon, though it later claimed it constructed several crude devices that it eventually dismantled. In the late 1970s
1970s
File:1970s decade montage.png|From left, clockwise: US President Richard Nixon doing the V for Victory sign after his resignation from office after the Watergate scandal in 1974; Refugees aboard a US naval boat after the Fall of Saigon, leading to the end of the Vietnam War in 1975; The 1973 oil...
American spy satellites detected a "brief, intense, double flash of light near the southern tip of Africa." Known as the Vela Incident
Vela Incident
The Vela Incident was an unidentified "double flash" of light that was detected by an American Vela Hotel satellite on September 22, 1979....
, it was speculated to have been a South African or possibly Israeli nuclear weapons test, though some feel that it may have been caused by natural events or a detector malfunction.
Israel
Israel
The State of Israel is a parliamentary republic located in the Middle East, along the eastern shore of the Mediterranean Sea...
is widely believed to possess an arsenal of potentially up to several hundred nuclear warheads, but this has never been officially confirmed or denied (though the existence of their Dimona nuclear facility
Negev Nuclear Research Center
The Negev Nuclear Research Center is an Israeli nuclear installation located in the Negev desert, about thirteen kilometers to the south-east of the city of Dimona. The purpose of Dimona is widely assumed to be the manufacturing of nuclear weapons, and the majority of defense experts have...
was confirmed by Mordechai Vanunu
Mordechai Vanunu
Mordechai Vanunu ; is a former Israeli nuclear technician who, citing his opposition to weapons of mass destruction, revealed details of Israel's nuclear weapons program to the British press in 1986. He was subsequently lured to Italy by a Mossad agent, where he was drugged and kidnapped by...
in 1986).
North Korea announced in 2003 that it also had several nuclear explosives though it has not been confirmed and the validity of this has been a subject of scrutiny amongst weapons experts. The first detonation of a nuclear weapon
Nuclear weapon
A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or a combination of fission and fusion. Both reactions release vast quantities of energy from relatively small amounts of matter. The first fission bomb test released the same amount...
by the Democratic People's Republic of Korea was the 2006 North Korean nuclear test
2006 North Korean nuclear test
The 2006 North Korean nuclear test was the detonation of a nuclear device conducted on October 9, 2006 by North Korea.North Korea announced its intention to conduct a test on October 3, six days prior, and in doing so became the first nation to give warning of its first nuclear test...
, conducted on October 9, 2006. On May 25, 2009 North Korea continued nuclear testing, violating United Nations Security Council Resolution 1718
United Nations Security Council Resolution 1718
United Nations Security Council Resolution 1718 was adopted unanimously by the United Nations Security Council on October 14, 2006. The resolution, passed under Chapter VII, Article 41, of the UN Charter, imposes a series of economic and commercial sanctions on the Democratic People's Republic of...
.
In Iran
Iran
Iran , officially the Islamic Republic of Iran , is a country in Southern and Western Asia. The name "Iran" has been in use natively since the Sassanian era and came into use internationally in 1935, before which the country was known to the Western world as Persia...
, Ayatollah
Ayatollah
Ayatollah is a high ranking title given to Usuli Twelver Shī‘ah clerics. Those who carry the title are experts in Islamic studies such as jurisprudence, ethics, and philosophy and usually teach in Islamic seminaries. The next lower clerical rank is Hojatoleslam wal-muslemin...
Ali Khamenei
Ali Khamenei
Ayatollah Seyed Ali Hoseyni Khāmene’i is the Supreme Leader of Iran and the figurative head of the Muslim conservative establishment in Iran and Twelver Shi'a marja...
issued a fatwa
Fatwa
A fatwā in the Islamic faith is a juristic ruling concerning Islamic law issued by an Islamic scholar. In Sunni Islam any fatwā is non-binding, whereas in Shia Islam it could be considered by an individual as binding, depending on his or her relation to the scholar. The person who issues a fatwā...
forbidding the production, stockpiling and use of nuclear weapons on August 9, 2005. The full text of the fatwa was released in an official statement at the meeting of the International Atomic Energy Agency (IAEA) in Vienna. Despite this, however, there is mounting concern in many nations about Iran's refusal to halt its nuclear power program, which many (including some members of the US government) fear is a cover for weapons development. (See Iran and weapons of mass destruction
Iran and weapons of mass destruction
Iran is not known to currently possess weapons of mass destruction and has signed treaties repudiating the possession of weapons of mass destruction including the Biological Weapons Convention, the Chemical Weapons Convention, and the Nuclear Non-Proliferation Treaty...
.)
- See also: Argentinian nuclear weapons programArgentina and weapons of mass destructionArgentina has a history with the development of weapons of mass destruction. Under the National Reorganization Process, Argentina began a nuclear weapons program in the early 1980s, and was abolished when democracy was restored in 1983....
- See also: Brazilian nuclear weapons programBrazil and weapons of mass destructionIn the 1970s and 80s, during the military regime, Brazil had a secret program intended to develop nuclear weapons. The program was dismantled in 1990, five years after the military regime ended, and Brazil is considered free of weapons of mass destruction....
- See also: Swedish nuclear weapon programSwedish nuclear weapon programDuring the 20th century Sweden had programs for both Nuclear and Chemical weapons. During the first decades of the Cold War a nuclear weapon program was active...
See also
- Albert EinsteinAlbert EinsteinAlbert Einstein was a German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and one of the most prolific intellects in human history...
- BrinkmanshipBrinkmanshipBrinkmanship is the practice of pushing dangerous events to the verge of disaster in order to achieve the most advantageous outcome...
- Brinkmanship (Cold War)Brinkmanship (Cold War)Brinkmanship is a term that was used to refer to the constant competition between the United States of America and the Soviet Union.-Origin:The the term "brinkmanship" was originally coined by United States Secretary of State John Foster Dulles during the height of the Cold War...
- National weapons programs:
- Manhattan ProjectManhattan ProjectThe Manhattan Project was a research and development program, led by the United States with participation from the United Kingdom and Canada, that produced the first atomic bomb during World War II. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the US Army...
(USA)- Los Alamos National LaboratoryLos Alamos National LaboratoryLos Alamos National Laboratory is a United States Department of Energy national laboratory, managed and operated by Los Alamos National Security , located in Los Alamos, New Mexico...
- prelude:
- Frisch-Peierls memorandumFrisch-Peierls memorandumThe Frisch–Peierls memorandum was written by Otto Frisch and Rudolf Peierls while they were both working at the University of Birmingham, England. The memorandum contained new calculations about the size of the critical mass needed for an atomic bomb, and helped accelerate British and U.S...
- MAUD CommitteeMAUD CommitteeThe MAUD Committee was the beginning of the British atomic bomb project, before the United Kingdom joined forces with the United States in the Manhattan Project.-Frisch & Peierls:...
- S-1 Uranium CommitteeS-1 Uranium CommitteeThe S-1 Uranium Committee was a Committee of the National Defense Research Committee that succeeded the Briggs Advisory Committee on Uranium and later evolved into the Manhattan Project.- World War II begins :...
- Frisch-Peierls memorandum
- Los Alamos National Laboratory
- German nuclear energy projectGerman nuclear energy projectThe German nuclear energy project, , was an attempted clandestine scientific effort led by Germany to develop and produce the atomic weapons during the events involving the World War II...
- Tube AlloysTube AlloysTube Alloys was the code-name for the British nuclear weapon directorate during World War II, when the development of nuclear weapons was kept at such a high level of secrecy that it had to be referred to by code even in the highest circles of government...
(UK) - Japanese atomic programJapanese atomic programThe Japanese program to develop nuclear weapons was conducted during World War II. Like the German nuclear weapons program, it suffered from an array of problems, and was ultimately unable to progress beyond the laboratory stage before the atomic bombings of Hiroshima and Nagasaki and the Japanese...
- Soviet atomic bomb projectSoviet atomic bomb projectThe Soviet project to develop an atomic bomb , was a clandestine research and development program began during and post-World War II, in the wake of the Soviet Union's discovery of the United States' nuclear project...
- Project-706Project-706Project-706, also known as Project-726 or as the Kahuta Project, was a science effort codename of a project conducted during the Cold War and Russo-Afghan War whose objective was to develop Pakistan' first atomic weapon. The mainstream goal of the project was the development of an atomic bomb using...
- Weapons of Mass DestructionWeapons of mass destructionA weapon of mass destruction is a weapon that can kill and bring significant harm to a large number of humans and/or cause great damage to man-made structures , natural structures , or the biosphere in general...
- Manhattan Project
- More information about nuclear weaponNuclear weaponA nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or a combination of fission and fusion. Both reactions release vast quantities of energy from relatively small amounts of matter. The first fission bomb test released the same amount...
s:- Nuclear explosionNuclear explosionA nuclear explosion occurs as a result of the rapid release of energy from an intentionally high-speed nuclear reaction. The driving reaction may be nuclear fission, nuclear fusion or a multistage cascading combination of the two, though to date all fusion based weapons have used a fission device...
- Nuclear testingNuclear testingNuclear weapons tests are experiments carried out to determine the effectiveness, yield and explosive capability of nuclear weapons. Throughout the twentieth century, most nations that have developed nuclear weapons have tested them...
- Nuclear weapon designNuclear weapon designNuclear weapon designs are physical, chemical, and engineering arrangements that cause the physics package of a nuclear weapon to detonate. There are three basic design types...
- Nuclear warfareNuclear warfareNuclear warfare, or atomic warfare, is a military conflict or political strategy in which nuclear weaponry is detonated on an opponent. Compared to conventional warfare, nuclear warfare can be vastly more destructive in range and extent of damage...
- Nuclear arms raceNuclear arms raceThe nuclear arms race was a competition for supremacy in nuclear warfare between the United States, the Soviet Union, and their respective allies during the Cold War...
- Nuclear proliferationNuclear proliferationNuclear proliferation is a term now used to describe the spread of nuclear weapons, fissile material, and weapons-applicable nuclear technology and information, to nations which are not recognized as "Nuclear Weapon States" by the Treaty on the Nonproliferation of Nuclear Weapons, also known as the...
- List of nuclear accidents
- List of nuclear tests
- List of nuclear weapons
- Nuclear explosion
External links
- Timeline of atomic age events
- Federation of American Scientists - Worldwide Nuclear Forces Guide
- The Genesis of the Atomic Bomb -
- Nuclear Weapons Archive - includes the nuclear weapon histories of many countries
- NDRC Nuclear Notebook: Nuclear pursuits - "Bulletin of the Atomic Scientists". Comparative table of the histories and arsenals of the five NPT-designated nuclear powers as of 1993.
- NuclearFiles.org Timeline- from Atomic Discovery to the 2000s
- NuclearFiles.org A comprehensive history of nuclear weapons, including Pre, During, and Post Cold War
- Nevada Desert ExperienceNevada Desert ExperienceThe Nevada Desert Experience is a name for the movement to stop U.S. nuclear weapons testing that came into use in the middle 1980s. It is also the name of a particular anti-nuclear organization which continues to create public events to question the morality and intelligence of the U.S. nuclear...
Nevada Desert Experience - Western States Legal Foundation Western States Legal Foundation
- Ariel E. Levite, "Heading for the Fourth Nuclear Age", Proliferation Papers, Paris, Ifri, Winter 2009
- The National Museum of Nuclear Science & History (United States) - located in Albuquerque, New Mexico; a Smithsonian Affiliate Museum