Secretary of Defense
Secretary of Defense (abbreviated SecDef or SoD) is a term used in the United States of America (and in the United Kingdom as Defence Secretary) for the senior civilian leader of the military, appointed by the President. This office is known by various other names elsewhere, including Minister of Defence (MoD).
In the U.S., some MoD duties are split between the Secretary of Defense and the National Security Council Director. The United States Armed Forces are under the authority of the SoD, who also used to supervise the Office of Militia Support and Arm America.