United States Air Force
The U.S. War Department created the first antecedent of the U.S. Air Force, as a part of the U.S. Army, on 1 August 1907, which through a succession of changes of organization, titles, and missions advanced toward eventual independence 40 years later. In World War II, almost 68,000 U.S. airmen died helping to win the war, with only the infantry suffering more casualties. In practice, the U.S. Army Air Forces (USAAF) was virtually independent of the Army during World War II, and in virtually all ways functioned as an independent service branch, but airmen still pressed for formal independence. The National Security Act of 1947 was signed on 26 July 1947 by President Harry S Truman, which established the Department of the Air Force, but it was not until 18 September 1947, when the first secretary of the Air Force, W. Stuart Symington, was sworn into office that the Air Force was officially formed as an independent service branch.
United States Air Force Security Forces
In June 1950 the Air Force began urgent operations focused on air base defense with the outbreak of the Korean War. A buildup of ground combat forces began. The center of this buildup was the expansion of the Air Force Air Police from 10,000 in July 1950 to 39,000 in December 1951. Still, one year into the war the Air Provost Marshal reported that "the Air Force is without policy or tactical doctrine for Air Base Ground Defense." In haste, Air Police serving as the cadre of this force were outfitted with armored vehicles, machine guns and recoilless rifles. Air base defense was officially implemented by Air Force Regulation (AFR) 355-4 on 3 March 1953. AFR 355-4 defined air base defense "as all measures taken by the installation commander to deny hostile forces access to the area encompassing all buildings, equipment, facilities, landing fields, dispersal areas and adjacent terrain." However, the regulation did not include provisions for sustained ground defense operations. Performance of this mission fell to the provisional base defense task forces to be organized and equipped like infantry. It was the Strategic Air Command's (SAC) October 1952 edition of the SAC Manual 205-2 that rejected the notion that the USAF's ground defense mission conflicted with Army functions. SAC officials felt that success of the Air Force mission might require point defense elements that the Army could not afford to protect, much less have the Air Force rely on the Army to come to the rescue. After the Korean War, General Curtis LeMay had the Air Police begin the Combat Arms Program, to better train airmen in the use of weapons.