Who founded a U.S. arms development firm that is best known for an American submachine gun, invented by John T. Thompson in 1918, that became infamous during the Prohibition era?
Colonel John T. Thompson
Title: United Defense M42
Passage: The United Defense M42, sometimes known as the Marlin for the manufacturer, was an American submachine gun in World War II.  It was produced from 1942 to 1943 by United Defense Supply Corp.  (a government-formed company specifically tasked with weapons development) for possible issue as a replacement for the Thompson submachine gun and was used by agents of the Office of Strategic Services (OSS).
Title: Auto-Ordnance Company
Passage: Auto-Ordnance was a U.S. arms development firm founded by retired Colonel John T. Thompson of the U.S. Army Ordnance Department in 1916.  Auto-Ordnance is best known for the Thompson submachine gun, notorious as a gangster weapon of the Roaring Twenties and famous as a military weapon of the Allied forces in World War II.
Title: Thompson submachine gun
Passage: The Thompson submachine gun is an American submachine gun, invented by John T. Thompson in 1918, that became infamous during the Prohibition era.  It was a common sight in the media of the time, being used by both law enforcement officers and criminals.  The Thompson submachine gun was also known informally as the "Tommy Gun", "Annihilator", "Chicago Typewriter", "Chicago Piano", "Chicago Style", "Chicago Organ Grinder", "Trench Broom", "Trench Sweeper", "The Chopper", and simply "The Thompson".
Thompson submachine gun Auto-Ordnance Company