World War II demonstrated how valuable air power was and the need to change the organization of the nation’s military forces. This resulted in the creation of a single Department of Defense with strong Joint Chiefs of Staff with Army, Navy, and Air Force chiefs.

The National Security Act, signed by President Harry S. Truman on July 26, 1947, established this new defense organization and the United States Air Force as an independent service, equal to the Army and Navy. On September 18, 1947, Chief Justice Fred Vinson administered the Oath of Office to Stuart Symington as the first Secretary of the Air Force, officially founding a new branch of the U.S. military on that day exactly 78 years ago this coming Thursday.

Read additional details about the Air Force’s founding and ways the anniversary can be recognized nationwide.