The United States Army (June 14, 1775) is a branch of the armed forces of the United States. The other four are the Navy (October 13, 1775), the Air Force (part of the Army until 1947), the Marines (November 10, 1775), and the Coast Guard (1790), leading to the symbolism of the shape of their administration building, the Pentagon. The US Army is the oldest of these five branches, and used to have its own cabinet department (the Department of War). Now, however, its administration falls under the auspices of the Department of Defense.The US Army is still the largest branch of the United States' armed forces.

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