Randolph said: "Doubtless DuBois is the only alleged leader of an oppressed group of people in the world today who condemns revolution." To Randolph, violence and revolution were not anti-American, but were justified by the Declaration of Independence. During the twenties, Randolph tried several schemes to increase black and white cooperation in unions. Along with Chandler Owen, he founded the National Association for the Promotion of Unionism among Negroes. The most successful of Randolph's efforts came in 1925 when he established the Brotherhood of Sleeping Car Porters. The Brotherhood appeared to demonstrate the futility of his basic thesis. Randolph, who believed in biracial unionism, had established, in the Brotherhood, an organization which, by the nature of the occupation, was to be an exclusively black union. He found himself being pushed relentlessly away from biracial unionism into supporting racial organizations for racial advancements. In 1936, he played a key role in forming the National Negro Congress. It was a broad alliance of all kinds of groups to advance the welfare of the race. Although it did not receive the backing of the N.A.A.C.P., the Urban League, an even more conservative organization, became a cornerstone in the Congress. The Urban League has always been primarily interested in securing employment for the Negro working class. During the thirties, the communists adopted a united-front policy, and they tried to infiltrate the N.N.C. Some of the left-wing unions which did support the N.N.C., were largely white. Randolph's talent for mass mobilization was demonstrated most clearly in his efforts to organize two gigantic marches on Washington in order to dramatize Afro-American needs and to pressure the government into action. As American industry began to gear up for war production at the beginning of the Second World War, it needed to find new sources of labor. The Afro-American community was eager to support the war effort, particularly because it meant fighting Hitler's racism. But they were also eager to find jobs. However, defense industries in America continued to display their own brand of racial discrimination. Many of them said quite openly that, while they were willing to hire blacks, they would only give them menial positions regardless of their skill and training. It became clear that racism had to be fought at home and abroad.