The Digital National Security Archive is an invaluable online collection of more than 100,000 declassified records documenting historic U.S. policy decisions.

DNSA provides authoritative access to the original documents—most of them formerly classified and previously unavailable—that underlie the crucial decisions facing presidents from Harry Truman to Barack Obama.

Researchers can directly access the documents that shaped responses to issues ranging from the origins of the Cold War to the terrorist attacks on the World Trade Center and the Pentagon, and beyond.