First U.S. aircraft carrier offensive of the war as YORKTOWN and ENTERPRISE conduct air raids on Japanese bases in the Gilbert and Marshall Islands.
Battle of Empress Augusta Bay.
The U.S. Army Air Force begins preparations for dropping the Atomic Bomb by establishing the 509th Composite Group to operate the B-29s that will deliver the bomb.
First Atomic Bomb dropped on Hiroshima from a B-29 flown by Col. Paul Tibbets.