The third camp, also known as third camp socialism or third camp Trotskyism, is a branch of socialism which aims to oppose both capitalism and Stalinism, by supporting the organised working class as a "third camp".
The term arose early during the Second World War, and refers to the idea of two "imperialist camps" competing to dominate the world: one led by the United Kingdom and France and supported by the United States, and the other led by Nazi Germany and supported by Fascist Italy.
From the 1930s and beyond, Leon Trotsky and his American acolyte James P. Cannon described the Soviet Union as a "degenerated workers' state," the revolutionary gains of which should be defended against imperialist aggression despite the emergence of a gangster-like ruling stratum, the party bureaucracy. While defending the Russian revolution from outside aggression, Trotsky, Cannon, and their followers at the same time urged an anti-bureaucratic political revolution against Stalinism to be conducted by the Soviet working class themselves.
Dissidents in the Trotskyist Socialist Workers Party, witnessing the collaboration of Joseph Stalin and Adolf Hitler in the invasion and partition of Poland and Soviet invasion of the Baltic states, argued that the Soviet Union had actually emerged as a new social formation, neither capitalist nor socialist. Adherents of this view, espoused most explicitly by Max Shachtman and closely following the writings of James Burnham and Bruno Rizzi, argued that the Soviet bureaucratic collectivist regime had in fact entered one of two great imperialist "camps" aiming to wage war to divide the world. The first of these imperialist camps, which Stalin and the Soviet Union were said to have joined as a directly participating ally, was headed by Nazi Germany and included most notably fascist Italy. The "second imperialist camp," in this original analysis, was headed by England and France, actively supported by the United States.