Later in his career, Reuther was faulted for his shift from the political left to a moderate position. This change included the adoption of a strong anti-Communist philosophy. All this was less sweeping than it seemed. What remained constant was Reuther’s strong belief in social democratic action: he had always rejected any political system based on totalitarian rule.
By the end of 1935, the Russian workers were trained and the Reuther brothers returned to Detroit just in time to participate in the great union-organizing struggles in the automobile industry. To more effectively "organize the unorganized," Walter Reuther worked to combine several small Detroit local unions into the Westside Local 174. He became president of the large local, and at the UAW’s 1936 convention, he was elected to the union’s executive board.
Success came rapidly to the UAW in 1937. General Motors and Chrysler recognized the union after sit-down strikes crippled their production. Henry Ford’s intractable resistance dashed all hopes of the third automobile giant quickly recognizing the UAW. Reuther would soon discover the extent of Ford’s anti-union tactics.
On May 26, 1937, Walter Reuther and other UAW organizers passed out leaflets at a pedestrian overpass next to the Ford Rouge factory complex in Dearborn, Michigan. What followed, now known as the "Battle of the Overpass," began when members of Ford’s private police organization, euphemistically called the Service Department, attacked the UAW group. "After they kicked me down all the stairs," Reuther recalled shortly after the battle, "they then started to hit me again...driving me before them." The incident was a public relations disaster for Henry Ford, but he continued to resist the UAW until April 1941, when a massive strike shut down the Ford Motor Company.
In 1939 Reuther was appointed the head of the General Motors department by UAW President R. J. Thomas. When General Motors stalled negotiations for a new union contract, Reuther called for a June strike, but only by tool-and-die workers. This tactic halted the all-important retooling for the 1940 model year. Faced with a production shutdown, General Motors agreed to a new contract.
Just before World War II, with almost half of the nation’s auto-manufacturing capacity idle, Reuther received national attention for his plan to use factories in Michigan and elsewhere to build five hundred military aircraft a day. Although technically feasible, the plan was never implemented because automakers resisted what they considered an attempt to dictate their production. However, during the war the industry did produce aircraft, tanks and other war material in unprecedented amounts.