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U.S. Department of Defense: Quick Facts

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News •

Hegseth and staff reprimanded by guard at Tomb of the Unknown Soldier • Nov. 11, 2026, 8:28 PM ET (AP)
Hegseth says bipartisan impeachment push is about ‘policy disagreements,’ not high crimes in rare Pentagon briefing • Nov. 10, 2026, 8:13 AM ET (AP)
New Pentagon directive bans troops from using nonpublic info to bet in prediction markets • Oct. 22, 2026, 5:42 PM ET (AP)

Facts

Also Known As DOD
Date 1947 - present
Areas Of Involvement national security • defense • Today in History—June 13: The Pentagon Papers Reach the Public • Today in History—May 16: The WWII Story That Inspired Saving Private Ryan • Why doesn’t the U.S. have a Department of War anymore?
Related People Pete Hegseth • William S. Cohen • Melvin Laird • James Mattis • Phebe Novakovic • Robert M. Gates • Michael Griffin • Daniel Ellsberg • Donald Rumsfeld • John M. Deutch • Les Aspin • James V. Forrestal

Photos

The Pentagon
The official seal of the United States Department of Defense features a bald eagle with outstretched wings holding arrows and an olive branch, surrounded by stars and a blue border with the words Department of Defense and United States of America.
President Harry S. Truman sits at his desk signing the National Security Act of 1947, with men in military uniforms and suits standing behind him.
President Barack Obama, seen from behind, leads a meeting with the Joint Chiefs of Staff and Secretary of Defense Robert M. Gates in the Oval Office.
National Security Agency
National Reconnaissance Office
A comparison chart displays the officer rank insignias for the United States Army, Marines, Air Force, Space Force, Navy, and Coast Guard, with each rank represented by its corresponding badge, bar, leaf, eagle, or star symbols.
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Related Topics and References

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