The Department of Defense is America's largest government agency. With our military tracing its roots back to pre-Revolutionary times, the department has grown and evolved with our nation. Our mission is to provide the military forces needed to deter war and ensure our nation's security.
National Defense Budget
Service Members & Civilians
In Over 160 Countries
The Army, Marine Corps, Navy, Air Force, Space Force and Coast Guard are the armed forces of the United States. The Army National Guard and the Air National Guard are reserve components of their services and operate in part under state authority.
The Defense Department has 11 combatant commands, each with a geographic or functional mission that provides command and control of military forces in peace and war.
Top civilian defense decision-makers work with the secretary to develop policy, operational and fiscal plans, manage resources and evaluate programs.
The Department of Defense is focused on the following areas:
Build a more lethal force.
Strengthen alliances and attract new partners.
Reform the department.
Supporting the military family.
The Department of Defense is America's oldest and largest government agency, tracing its roots back to pre-Revolutionary times. Learn about DOD’s rich history and innovations.
The Pentagon, with its iconic design, is the headquarters of the Department of Defense. Find out more about DOD’s mission and organization.
You have questions. We have answers. Search our most frequently asked questions.
Can’t find an answer in our FAQs? Please use our contact form.
Covering the defense beat and the Pentagon? Here's what you need to know.
The Department of Defense provides the military forces needed to deter war and ensure our nation's security.