United States Secretary of the Navy
The Secretary of the Navy (or SECNAV) is a statutory office (10 U.S.C. § 5013) and the head (chief executive officer) of the Department of the Navy, a military department (component organization) within the Department of Defense of the United States of America.
The Secretary of the Navy must by law be a civilian, at least 5 years removed from active military service, and is appointed by the President and requires confirmation by a majority vote of the Senate.
The Secretary of the Navy was, from its creation in 1798, a member of the President's Cabinet until 1949, when the Secretary of the Navy (and the Secretaries of the Army and Air Force) was by amendments to the National Security Act of 1947 made subordinate to the Secretary of Defense.
Responsibilities
The Department of the Navy (DoN) consists of two Uniformed Services: the United States Navy and the United States Marine Corps. The Secretary of the Navy is responsible for, and has statutory authority (10 U.S.C. § 5013) to "conduct all the affairs of the Department of the Navy", i.e. as its chief executive officer, subject to the limits of the law, and the directions of the President and the Secretary of Defense. In effect, all authority within the Navy and Marine Corps, unless specifically exempted by law, is derivative of the authority vested in the Secretary of the Navy.