Indispensable reading for all those seeking a serious analysis of the central political problems confronting the working class in the latter half of the twentieth century and today. This Marxist polemic reviews the political and theoretical disputes inside the Fourth International, the international Marxist movement founded by Leon Trotsky in 1938, and gives a detailed objective assessment of the political contribution and evolution of James P. Cannon, Trotsky's most important cothinker in the US Based on extensive research, with detailed references to original documents and programmatic statements from the archives of the Trotskyist movement..