Terrorism is the systematic use of terror, especially as a means of coercion
Coercion is the practice of forcing another party to behave in an involuntary manner by use of threats or intimidation or some other form of pressure or force. In law, coercion is codified as the duress crime. Such actions are used as leverage, to force the victim to act in the desired way...

. In the international community
International community
The international community is a term used in international relations to refer to all peoples, cultures and governments of the world or to a group of them. The term is used to imply the existence of common duties and obligations between them...

, however, terrorism has no universally agreed, legally binding, criminal law definition. Common definitions of terrorism refer only to those violent acts which are intended to create fear (terror), are perpetrated for a religious, political or, ideological goal; and deliberately target or disregard the safety of non-combatant
Non-combatant is a term in the law of war describing civilians not taking a direct part in hostilities, as well as persons such as medical personnel and military chaplains who are regular soldiers but are protected because of their function as well as soldiers who are hors de combat ; that is, sick,...

s (civilians).

“I Define a “terrorist” as a non-state actor who attacks civilian targets in order to strike terror into the hearts of the enemy community.. A “state terrorist” is a state doing the same thing.

Michael Mann, Professor of Sociology, UCLA in ‘Incoherent Empire’, p 159

[R]efusing to accept a life of submission, the suicide bomber turns life itself into a horrible weapon.

Michael Hardt and Antonio Negri, Multitude