Fleet Marine Force (FMF) Core 103 USMC Mission and Organization Practice Test

Civilian leadership directs the duties of the Navy and Marine Corps. In the chain of authority, the President serves as Commander in Chief, but day-to-day directives for Navy and Marine Corps units come through the civilian head of the department—the Secretary of the Navy. The Secretary of Defense oversees the entire DoD, but it is the Secretary of the Navy who directly directs the duties of naval and Marine Corps forces within their jurisdiction. The Commandant of the Marine Corps carries out those directives under the Secretary’s authority, not as the originator of all duties. Hence, duties may be directed by the Secretary of the Navy.