The United States National Guard is part of the reserve components of the United States Army and the United States Air Force. It is a military reserve force composed of National Guard military members or units of each state and the territories of Guam, the Virgin Islands, and Puerto Rico, and the District of Columbia, for a total of 54 separate organizations. All members of the National Guard of the United States are also members of the Organized Militia of the United States as defined by 10 U.S.C. § 246.