The latest news and top stories on the US Department of Defense. A prominent Arlington, Virginia-based executive department of the U.S. federal government, the US Department of Defense (DoD) is dedicated to providing the military forces necessary to deter war and ensure national security. Its main areas of focus include coordinating and supervising the armed services, developing military policies, and engaging in global defence, humanitarian aid, and cyber operations. Established in 1947, the DoD is America’s largest government agency, playing a crucial role in protecting U.S. interests and allies worldwide.