In the U.S. military chain of command, who has the authority to direct Combatant Commands?

• A. The President
• B. The Secretary of Defense
• C. The Chairman of the Joint Chiefs of Staff
• D. The Commander of US Forces in Europe

Answer: (B)

The key idea is how command flows in the U.S. military. Combatant Commands fall under the authority of the Secretary of Defense, who directs their activities and assigns missions through the Unified Command Plan. The President, as Commander in Chief, sets policy and can direct actions, but the day-to-day and the formal direction of Combatant Commands come through the Secretary of Defense. The Chairman of the Joint Chiefs of Staff serves as the senior military adviser, not as the operational commander with authority over all combatant commands. A regional commander, like the one in Europe, leads forces within that theater but does not have authority to direct every Combatant Command. This structure—President’s strategic leadership, Secretary of Defense's control over Combatant Commands, and the Chairman’s advisory role—explains why the Secretary of Defense is the authority who directs Combatant Commands.