Which of the following is a JCS responsibility?

• A. Draft international treaties.
• B. Direct combat operations.
• C. Establish joint doctrine and review major materiel and personnel requirements.
• D. Domestic policing and law enforcement oversight.

Answer: (C)

The JCS shapes how the armed forces fight together by establishing joint doctrine and reviewing major materiel and personnel requirements, ensuring interoperability and the right resources for unified action. Creating joint doctrine gives every service common methods and language for planning, training, and executing operations, so forces from different branches can operate as a coordinated whole. Reviewing major materiel and personnel requirements means evaluating programs and budgets to ensure the right equipment and manpower are in place and prioritized to meet strategic needs. This function sits squarely in strategic oversight and planning, not in drafting international treaties, directing combat operations, or domestic policing, which are handled by diplomats, combatant commanders in the field, or civilian law enforcement agencies, respectively.