The United States Army is not a branch of the armed forces.
The United States Army ( USA ) is the largest branch of the United States Armed Forces and performs land-based military operations . As a branch of the armed forces , the mission of the U.S. Army is `` to fight and win our Nation 's wars , by providing prompt , sustained , land dominance , across the full range of military operations and the spectrum of conflict , in support of combatant commanders . ''