James Cannon, the first chairman of the American Communist Party, attended the Sixth Congress of the Comintern in 1928. While in the Soviet Union he was given a document written by Leon Trotsky on the rule of Joseph Stalin. Convinced by what he read, when he returned to the United States he criticized the Soviet government. As a result of his actions, Cannon and his followers were expelled from the party.
James Cannon, Max Shachtman and Martin Abern now joined with other Trotskyists to form the Communist League of America. Cannon now joined with other Trotskyists to form the Communist League of America. They also published the journal, The Militant. Cannon later recalled. "I never deceived myself for a moment about the most probable consequences of my decision to support Trotsky in the summer of 1928. I knew it was going to cost me my head and also my swivel chair, but I thought: What the hell-better men than I have risked their heads and their swivel chairs for truth and justice. Trotsky and his associates were doing it at that very moment in the exile camps and prisons of the Soviet Union. It was no more than right that one man, however limited his qualifications, should remember what he started out in his youth to fight for, and speak out for their cause and try to make the world hear, or at least to let the exiled and imprisoned Russian Oppositionists know that they had found a new friend and supporter."
According to Joseph Leroy Hansen: "The document completely convinced Cannon. He decided to battle for Trotsky's criticisms - not because of any hope of immediate success, but because he saw that Trotsky was right. It was not an easy decision. Cannon realized, perhaps better than anyone outside of the Russian Trotskyists, that it would mean ostracism, the breakup of old friendships, and the end of personal relations with many comrades he had known in common battles for years. However, it was politically necessary to make the turn. For Jim this consideration was paramount. Nothing personal could be permitted to stand in the way of moving ahead in defense of Trotsky's position and against Stalin's bureaucratic gang."
In December 1933, a group of radicals including Sidney Hook, Louis Budenz, James Rorty, V.F. Calverton, George Schuyler, James Burnham, J. B. S. Hardman and Gerry Allard formed the American Workers Party (AWP). Hook later argued: "The American Workers Party (AWP) was organized as an authentic American party rooted in the American revolutionary tradition, prepared to meet the problems created by the breakdown of the capitalist economy, with a plan for a cooperative commonwealth expressed in a native idiom intelligible to blue collar and white collar workers, miners, sharecroppers, and farmers without the nationalist and chauvinist overtones that had accompanied local movements of protest in the past. It was a movement of intellectuals, most of whom had acquired an experience in the labor movement and an allegiance to the cause of labor long before the advent of the Depression."
Soon after its formation of the AWP, leaders of the Communist League of America (CLA), a group that supported the theories of Leon Trotsky, suggested a merger. Sidney Hook, James Burnham and J. B. S. Hardman were on the negotiating committee for the AWP, Max Shachtman, Martin Abern and Arne Swabeck, for the CLA. Hook later recalled: "At our very first meeting, it became clear to us that the Trotskyists could not conceive a situation in which the workers' democratic councils could overrule the Party or indeed one in which there would be plural working class parties. The meeting dissolved in intense disagreement." However, despite this poor beginning, the two groups merged in December 1934.
in 1934 the party merged with the American Workers Party, to form the Workers Party of the United States, under the joint leadership of Cannon and Abraham Muste. The party was dissolved in 1936 when it was decided that members should join the successful Socialist Party of America.
James Cannon was arrested under the Alien Registration Act in 1941. He was detained in Sandstone Prison and was not released until 1945. Cannon remained as national secretary of the Socialist Workers Party until replaced by Farrell Dobbs in 1953. Dobbs was the SWP's presidential candidate in 1960 but received only 60,166 votes. He retired as the SWP's national secretary in 1972.