Operation Underworld was the United States government's code name for the cooperation of Italian and Jewish organized crime figures from 1942 to 1945 to counter Axis spies and saboteurs along the U.S. northeastern seaboard ports, avoid wartime labor union strikes, and limit theft by black-marketeers of vital war supplies and equipment.
(From: https://www.history.com/news/what-was-operation-underworld)
In the midst of the brutal conflict of WWII, U.S. Naval Intelligence was forced to make a deal with the mafia to protect its ports from enemy spies operating on American soil.
Video on how Lucky Luciano and the Mafia helped America beat the Nazis
