The United States Armed Forces are the military forces of the United States. They consist of the Army, Navy, Marine Corps, Air Force, and Coast Guard. The United States has a strong tradition of civilian control of the military. The President is the overall head of the military, and helps form military policy with the United States Department of Defense (DoD), a federal executive department, acting as the principal organ by which military policy is carried out. The DoD is headed by the Secretary of Defense, who is a civilian and Cabinet member. The Secretary of Defense is second in the military's chain of command, just below the President, and serves as the principal assistant to the President in all matters related to the Department of Defense.To coordinate military action with diplomacy, the President has an advisory National Security Council headed by a National Security Advisor. Both the President and Secretary of Defense are advised by a seven-member Joint Chiefs of Staff, which includes the head of each of Department of Defense service branches as well as the chief of the National Guard Bureau. Leadership is provided by the Chairman of the Joint Chiefs of Staff and the Vice Chairman of the Joint Chiefs of Staff.The Commandant of the Coast Guard is not a member of the Joint Chiefs of Staff.

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