Peter Drucker- Ch. 9/9 Max Shachtman and his Left, "The "American Century"" (1994)
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"The Workers Party (WP) was a Third Camp Trotskyist group in the United States. It was founded in April 1940 by members of the Socialist Workers Party who opposed the Soviet invasion of Finland and Leon Trotsky's belief that the USSR under Joseph Stalin was still innately proletarian, a "degenerated workers' state." They included Max Shachtman, who became the new group's leader, Hal Draper, C. L. R. James, Raya Dunayevskaya, Martin Abern, Joseph Carter, Julius Jacobson, Phyllis Jacobson, Albert Glotzer, Stan Weir, B. J. Widick, James Robertson, and Irving Howe. The party's politics are often referred to as "Shachtmanite.""