what is the role of the senate armed forces committee?

Answer 1

The Senate committee on military affairs determine what country will be invaded next.

Answer 2

There is not a Senate Armed Forces Committee. You are probably thinking of the Senate Committee on Armed Services Their responsibilities are:

Aeronautical and space activities peculiar to or primarily associated with the development of weapons systems or military operations; the common defense; the Department of Defense, the Department of the Army, the Department of the Navy, and the Department of the Air Force, generally; maintenance and operation of the Panama Canal, including administration, sanitation, and government of the Canal Zone; military research and development; national security aspects of nuclear energy; naval petroleum reserves, except those in Alaska; pay, promotion, retirement, and other benefits and privileges of members of the Armed Forces, including overseas education of civilian and military dependents; selective service system; and strategic and critical materials necessary for the common defense.
Comprehensive study and review of matters relating to the common defense policy of the United States.
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