Butch O'Hare's parents were separated so he grew up in Chicago, St. Louis, and Alton, Illinois. His father owned Sportsman's Park Racetrack and endangered his life in 1931 when he helped federal prosecutors build a case against Al Capone during Capone's trial for income tax evasion. Butch got an appointment to the U.S. Naval Academy at Annapolis, Maryland but lost his father to a gangland execution in 1939. In 1942, O'Hare became the first Navy ace of World War II.
According to his commandin officer, Butch O'Hare by himself "outnumbered" a squadron of six Japanese bombers threatening his aircraft carrier, the USS Lexington, near the Marshall Islands in the South Pacific in early 1942. Butch shot down five Japanese planes in about five minutes and saved his ship and 3,000 crew mates. President Franklin D. Roosevelt praised his bravery. FDR promonted Butch and gave him the Medal of Honor in 1942 but Butch was killed in action in 1943. O'Hare International Airport in Chicago, the old Orchard Field (ORD), was named in honor of Butch O'Hare in 1949 at the urging of Col. Robert McCormick, publisher of The Chicago Tribune.