The Constitution recognizes the necessity of defending ourselves as a free people. Article I gives Congress power to raise and maintain an army, and Article II names the president “commander in chief” of the military. In times of war, the division of power between the president and Congress often becomes a point of contention. The Constitution also ensures the military cannot be turned against the citizenry and allows citizens freedom to express their opinions about war.

From the constitution

Articles and amendments related to Military.

The Articles

The Amendments