Hoffa worked to defend the Teamsters from raids by other unions, including the Congress of Industrial Organizations, and he extended the Teamsters' influence in the Midwest 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 later advanced to become head of the Michigan Teamsters groups. Meanwhile, Hoffa obtained a deferment from military service in World War II by successfully making a case for his union leadership skills being of more value to the nation by keeping freight running smoothly to assist the war effort.
