Jimmy Hoffa IBT would expand as the union itself grew. Hoffa worked to defend the Teamsters unions from raids by other unions, including the CIO, and extended the Teamsters' influence in the Midwestern states, from the late 1930s to the late 1940s. Although he never actually worked as a truck driver, he became president of Local 299 in December 1946. He then rose to lead the combined group of Detroit-area locals shortly afterwards, and advanced to become head of the Michigan Teamsters groups sometime later. During this time, Hoffa obtained a deferment from military service in World War II by successfully making
Jimmy Hoffa assaulted. The threats from the mafia that they would get rid of Hoffa were taken very seriously; Hoffa's son is quoted as saying "Dad was pushing so hard to get back in office, I was increasingly afraid that the mob would do something about it." There had been three visits in a short time frame to Hoffa's home at Lake Orion and one trip to the Guardian Building law offices by Anthony Giacalone, an alleged kingpin in the Detroit Mafia, and his younger brother, Vito. Friendly with Provenzano and believed to be related to him, their avowed purpose in coming