Decision Maker

Department of Defense

The Department of Defense (DoD) is a key executive branch of the U.S. government responsible for implementing policies related to the country's military and ensuring the nation's defense. It oversees all branches of the U.S. military — the Army, Navy, Air Force, Marines, and Coast Guard — and manages national security and defense strategies. The DoD is also in charge of handling military intelligence, maintaining nuclear deterrence, and coordinating with other federal agencies on homeland security. Defense Secretary, appointed by the President with Senate confirmation, heads it, making it the largest employer in the world.