Navy, Department of the, is a military department within the Department of Defense of the United States government. The department is responsible for having naval and marine forces trained and ready to carry out military missions ordered by the president or the secretary of defense.
The Department of the Navy has three parts: (1) the Navy Department, (2) the Operating Forces, and (3) the Shore Establishment. The Navy Department is the central executive authority of the U.S. Navy. It is composed of the headquarters of the Navy and the U.S. Marine Corps in Washington, D.C. The Operating Forces consists of the fleets, including the Fleet Marine Forces, and other major sea commands. The U.S. Coast Guard functions as part of the Operating Forces in wartime or as directed by the president. The Shore Establishment operates within the United States. It performs a variety of technical activities that support the department’s Operating Forces.
The secretary of the Navy heads the Department of the Navy, under the direction of the secretary of defense. The secretary of the Navy ranks equally with secretaries of the Army and the Air Force. The position carries general responsibility for all naval affairs. The principal civilian aides of the secretary of the Navy are an undersecretary, a deputy undersecretary, and four assistant secretaries.
The chief of naval operations, an admiral, is the Navy’s highest-ranking military officer and a member of the Joint Chiefs of Staff. The chief is the principal naval adviser to the president and the secretary of the Navy on matters of war and the principal adviser and assistant to the secretary of the Navy.
The commandant of the Marine Corps is responsible for Marine Corps activities and is also a member of the Joint Chiefs of Staff. The commandant reports directly to the secretary of the Navy.
The United States Congress authorized the establishment of the Navy Department in 1798. As a result of the National Security Act of 1947, the Navy Department was renamed the Department of the Navy in 1949. That same year, it was placed under the direction of the Department of Defense.