Answer:The Department of Defense (DoD) is responsible for providing military force to ensure the nation's security. Established in 1949, it is the oldest and largest executive department of the United States federal government, employing more than 2.8 million individuals as of December 2016. The stated mission of the department is "to provide the military forces needed to deter war and to protect the security of our country." Major divisions of the department include the United States Army, Navy, and Air Force.
