“Military reserve organization The National Guard is a military reserve organization of the United States Department of Defense (DoD). It is composed of reserve components of the United States Army and the United States Air Force: the Army National Guard and the Air National Guard, respectively. It is based in each of the 50 U.S. states, the District of Columbia, and three U.S. territories. Guard components are part of the U.S. Army and the U.S. Air Force when activated for federal missions.”