Communist left in the context of "Left wing"

Socialism in one country was a Soviet state policy to strengthen socialism within the country rather than socialism globally. Given the defeats of the 1917–1923 European communist revolutions, Joseph Stalin developed and encouraged the theory of the possibility of constructing socialism in the Soviet Union alone. The theory was eventually adopted as Soviet state policy.

As a political theory, its exponents argue that it contradicts neither world revolution nor world communism. The theory opposes Leon Trotsky's theory of permanent revolution and the communist left's theory of world revolution.

World revolution is the Marxist concept of overthrowing capitalism in all countries through the conscious revolutionary action of the organized working class. For theorists, these revolutions will not necessarily occur simultaneously, but where and when local conditions allow a revolutionary party to successfully replace bourgeois ownership and rule, and install a workers' state based on social ownership of the means of production. In many Marxist schools, such as Trotskyism and communist left, the essentially international character of the class struggle and the necessity of global scope are critical elements and a chief explanation of the failure of socialism in one country.

The end goal of such internationally oriented revolutionary socialism is to achieve world socialism, and later, a communist society.