Doolittle, the only non-regular officer to command a major combat Air Force, began his military aviation career in 1917 in the Army Air Service of the United States. In 1922 he made the first flight across the continent of North America in less than 24 hours. Then followed a period of highly successful air racing. Working as an experimental engineer in the Air Corps Materiel Division, he played a major part in the development of aircraft instruments, making the first successful flight using these devices. He was awarded the Harmon Trophy in 1930 in recognition of this work.
Having left the Air Corps of the US Army in 1930 he returned in 1940 as a Major with the unenviable job of converting the automobile industry to aircraft production. In 1942 he led the raid on Tokyo in which squadrons of B- 25s were launched from aircraft carriers and landed on airfields in China. Although the military results of this raid were of little or no consequence the strategic impact on the Japanese was awesome: the Japanese Navy had allowed the enemy to get close enough to launch an attack on the Imperial capital and therefore on the Emperor. So great was the IJN’s loss of face that it soughtsettlement with the United States Navy in April 1942. (After Coral Sea and Midway, the Air Striking Force of the Imperial Japanese Navy never again threatened the US on equal terms.) Doolittle received the Medal of Honor for his actions in the Tokyo raid.
In 1942 Doolittle was given command of the US 12th Air Force in preparation for Operation Torch, the Allied invasion of North Africa. In 1943 he became Commander of the Northwest African Strategic Air Force, part of the Mediterranean Air Command. In 1944 Doolittle became a Lieutenant General and was created an Honorary KCB by King GEORGE VI.
In 1944 he was given command of the 8th Air Force which carried out the strategic bombing campaign against Germany and bombed the flying-bomb bases prior to D-Day. In 1945 Doolittle and his 8th Air Force sought action in the Pacific and enjoyed equal success against the Japanese.
Skillful, aggressive and versatile, Doolittle was admired by his men and colleagues.