The chairman of the Joint Chiefs of Staff (CJCS) is the presiding officer of the United States Joint Chiefs of Staff (JCS). The chairman is the highest-ranking and most senior military officer in the United States Armed Forces and the principal military advisor to the president, the National Security Council, the Homeland Security Council, and the secretary of defense. While the chairman of the Joint Chiefs of Staff outranks all other commissioned officers, the chairman is prohibited by law from having operational command authority over the armed forces; however, the chairman assists the president and the secretary of defense in exercising their command functions. The chairman convenes the meetings and coordinates the efforts of the Joint Chiefs, an advisory body within the Department of Defense comprising the chairman, the vice chairman of the Joint Chiefs of Staff, the chief of staff of the Army, the commandant of the Marine Corps, the chief of naval operations, the chief of staff of the Air Force, the chief of space operations, and the chief of the National Guard Bureau. The post of a statutory and permanent Joint Chiefs of Staff chair was created by the 1949 amendments to the National Security Act of 1947. The 1986 Goldwater–Nichols Act elevated the chairman from the first among equals to becoming the "principal military advisor" to the president and the secretary of defense. The Joint Staff, managed by the director of the Joint Staff and consisting of military personnel from all the services, assists the chairman in fulfilling his duties to the president and secretary of defense, and functions as a conduit and collector of information between the chairman and the combatant commanders. The National Military Command Center (NMCC) is part of the Joint Staff operations directorate (J-3). Although the office of Chairman of the Joint Chiefs of Staff is considered very important and highly prestigious, neither the chairman, the vice chairman, nor the Joint Chiefs of Staff as a body has any command authority over combatant forces. The Goldwater–Nichols Act places the operational chain of command from the president to the secretary of defense directly to the commanders of the unified combatant commands. However the service chiefs do have authority over personnel assignments and oversight over resources and personnel allocated to the combatant commands within their respective services (derived from the service secretaries). The chairman may also transmit communications to the combatant commanders from the president and secretary of defense as well as allocate additional funding to the combatant commanders if necessary. The chairman also performs all other functions prescribed under 10 U.S.C. § 153 or allocates those duties and responsibilities to other officers in the joint staff.
