The 3rd Marine Expeditionary Brigade is a United States Marine Corps

United States Marine Corps

The United States Marine Corps is a branch of the United States Armed Forces responsible for providing power projection from the sea, using the mobility of the United States Navy to deliver combined-arms task forces rapidly. It is one of seven uniformed services of the United States...

 unit that is the "middleweight" crises response force of choice in the Pacific Area of Operation. It is the Marine Corps’ only permanently forward-deployed Brigade sized Marine Air-Ground Task Force

Marine Air-Ground Task Force

The Marine Air-Ground Task Force is a term used by the United States Marine Corps to describe the principal organization for all missions across the range of military operations. MAGTFs are a balanced air-ground, combined arms task organization of Marine Corps forces under a single commander that...

, is a force in readiness able to deploy rapidly by any and all means and conduct operations across the spectrum from humanitarian assistance and disaster relief to amphibious assault and high intensity combat.