Joseph Carroll (DIA)
When the U.S. Air Force was established as a separate executive department under the National Security Act of 1947, Secretary of the Air Force W. Stuart Symington, requested FBI Director J. Edgar Hoover to loan General Carroll to the services to organize a U.S. Air Force agency for investigative and counterintelligence functions. He organized and directed this new organization, the AFOSI, along the lines of the FBI rather than the U.S. Army's Criminal Investigation Command (USACIDC or CID). General Carroll was tendered a commission as a colonel, U.S. Air Force Reserve, January 12, 1948. He was ordered to active duty in the grade of brigadier general May 6, 1948, and promoted to major general August 11, 1950.
History of the US Army National Guard
The 1947 Act also created the United States Air Force as a military service separate from the United States Army, of which it had been part since before World War I.