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The U.S. military chain of command is headed by the President of the United States, who serves as the Commander-in-Chief.  

All command authority flows from the President to the Secretary of Defense, who is a civilian and the principal assistant to the President in all matters related to the Department of Defense (also referred to as the Department of War).  

Below the Secretary of Defense, the chain splits into two distinct branches: one for operations and one for administrative functions.  

Key Leadership (as of October 2025)

• **Commander-in-Chief (President): Donald J. Trump  

• Secretary of Defense: Pete Hegseth  

• Chairman of the Joint Chiefs of Staff: Gen. Dan Caine, USAF  

1. Operational Chain of Command

This is the chain used to conduct military operations. It is straightforward and runs directly from the President to the commanders in the field.

1. President

2. Secretary of Defense

3. Combatant Commanders (CCDRs)  

Notice that the Joint Chiefs of Staff are not in this chain. Their role is advisory. The CCDRs are the generals and admirals who command all U.S. forces within their specific geographic or functional area of responsibility.  

There are 11 Unified Combatant Commands:  

• 6 Geographic Commands:  

• U.S. Africa Command (AFRICOM)  

• U.S. Central Command (CENTCOM)  

• U.S. European Command (EUCOM)  

• U.S. Indo-Pacific Command (USINDOPACOM)  

• U.S. Northern Command (NORTHCOM)  

• U.S. Southern Command (SOUTHCOM)  

• 5 Functional Commands:

• U.S. Cyber Command (CYBERCOM)  

• U.S. Special Operations Command (SOCOM)  

• U.S. Space Command (SPACECOM)  

• U.S. Strategic Command (STRATCOM)  

• U.S. Transportation Command (USTRANSCOM)  

2. Administrative Chain of Command

This parallel chain is used to "organize, train, and equip" the military services. Its job is to raise and maintain the armed forces, which are then assigned to the Combatant Commanders for operations.

1. President

2. Secretary of Defense

3. Secretaries of the Military Departments (These are civilian leaders)  

• Secretary of the Army  

• Secretary of the Navy  

• Secretary of the Air Force  

4. Service Chiefs (These are the highest-ranking military officers within each service)

• Chief of Staff of the Army  

• Chief of Naval Operations  

• Chief of Staff of the Air Force  

• Commandant of the Marine Corps  

• Chief of Space Operations  

The Role of the Joint Chiefs of Staff

It's a common misconception that the Chairman of the Joint Chiefs of Staff is the top commander.

• The Chairman (currently Gen. Dan Caine) is the highest-ranking military officer in the armed forces, but he has no command authority over operational forces.  

• The Chairman and the Joint Chiefs of Staff (which includes all the Service Chiefs) serve as the principal military advisors to the President and the Secretary of Defense.  

• Their primary job is to ensure the readiness of the forces and to develop strategic plans, fitting within the administrative side of the chain.