Updated

Running from the president to the secretary of defense to the commander of the combatant command, the chain of command for the United States military is spelled out by the Goldwater-Nichols Department of Defense Reorganization Act of 1986. The secretaries of the military departments assign all forces under their jurisdiction to the unified and specific combatant commands to perform missions assigned by those commands.

Under the Department of Defense Reorganization Act of 1958, the Departments of Army, Navy and Air Force were eliminated from the chain of "operational" command. Commanders of unified and specified commands now respond to the president and the secretary of defense through the joint chief of staff. The act redefined the functions of the military departments to those of essentially organizing, training, equipping and supporting combat forces for the unified and specified commands.

President of the United States
• Commander in chief of the United States Armed Forces.

Secretary of Defense
• Principal defense policy adviser to the president
• Appointed by the president and confirmed by the Senate
• Military action taken by the president is passed through the secretary of defense

National Security Council
• Consists of the president, vice-president, secretary of state and secretary of defense
• Serves as the principal forum for considering national security issues requiring presidential decisions
• The chairman of the joint chiefs of staff serves as military adviser to the Council; the CIA is the intelligence adviser
• The secretary of the treasury, the U.S. representative to the United Nations, the assistant to the president for national security affairs, the assistant to the president for economic policy and the president's chief of staff are invited to all meetings.
• The attorney general and the director of the office of national drug control policy attend meetings pertaining to their jurisdiction. If appropriate, other officials are invited.

Secretaries of the Military Departments
• The secretary assigns all forces to combatant commands except those assigned to recruit, organize, supply, equip, train, service, mobilize, administer and maintain their respective forces.
• Secretaries are appointed by the president and confirmed by the Senate.

Chairman of the Joint Chiefs of Staff [CJCS]
• The chairman is the principal military adviser to the president, secretary of defense and National Security Council.
• In carrying out these duties the chairman will consult and seek advice from the other service chiefs and combatant commanders as necessary.
• The chairman is appointed by the president and confirmed by the Senate for a four-year term

The Joint Chiefs of Staff
• Comprised of representatives of the Army, Navy, Marine Corps and Air Force.
• They have no executive authority to command combatant forces.
• Each of the chiefs is appointed by the president and confirmed by the Senate.

Unified and Specified Operations
• "Unified Commands" consist of elements from two or more services placed under a single commander who exercises operational control over the forces assigned to him.
• Service forces may be organized under subordinate joint commands.
• Specified commands have a broad continuing mission and are normally composed of forces primarily from one service. Within these unified and specified organizations, each military department (Army, Navy and Air Force) retains responsibility for administration and logistical support of its assigned forces under the directive authority of the CINC.

Combined Operations
• Conducted by forces of two or more nations, acting together toward the same objective.
• American forces participating in combined operations are subject to command arrangements and authorities established by international agreement between the participating nations.
• There are two types of combined operations: operations in which an alliance exists, characterized by formal agreements and procedures for coordination between forces, and operations in which a coalition exists with forces of nations friendly to the immediate undertaking. Coalition missions operate without prior formal agreements or procedures for coordination and are the most challenging. They require, at a minimum, require the support of an extensive liaison structure.