Who is the principal assistant to the President regarding the Department of Defense?

• A. Chairman of the Joint Chiefs of Staff
• B. National Security Advisor
• C. Secretary of Defense
• D. Secretary of the Navy

Answer: (C)

The principal civilian leader who represents the President on defense matters and runs the Department of Defense is the Secretary of Defense. This official oversees policy, planning, and the budget for the entire DoD and sits at the top of the civilian chain of command for the armed forces, coordinating with the services to ensure actions align with national strategy. The Chairman of the Joint Chiefs of Staff is the senior military adviser who provides military guidance to the President and the Secretary of Defense, but does not run the department. The National Security Advisor coordinates cross-agency national security policy, not the DoD’s day-to-day management. The Secretary of the Navy governs only one service within the department, not the whole department. Thus, the Secretary of Defense is the correct answer.