The Air National Guard (ANG), also known as the Air Guard, is a federal military reserve force as well as the militia air force of each U.S. state, the District of Columbia, the Commonwealth of Puerto Rico, and the territories of Guam and the U.S. Virgin Islands. It, along with each state's, district's, commonwealth's or territory's Army National Guard component, makes up the National Guard of each state and the districts, commonwealths and territories as applicable.
When Air National Guard units are used under the jurisdiction of the state governor they are fulfilling their militia role. However, if federalized by order of the President of the United States, ANG units become an active part of the United States Air Force
