Lenin, World War I and the social roots of opportunism

Leninism became fully recognized as an extension of Marxism after the success of the Russian Revolution in 1917. Throughout the world, the mass socialist parties and working class anarchist trends went through major political convulsions. New revolutionary parties, seeking to base themselves on the political and organizational lessons learned from the Bolshevik victory, were created in country after country as the left-wing socialists and anarchists split from established socialist parties and organizations to form communist parties. But the arrival of Leninism or Bolshevism as a distinctive international extension of Marxism, in direct opposition to the accepted Marxism of the Second International, actually took shape not at the time of revolutionary victory in 1917. Rather, it happened in a period of deepest reaction: at the very start of World War I. In 1914, V.I. Lenin broke openly with “official” socialism and Marxism, declaring that the leaders of the mass socialist parties who supported their own governments at the outbreak of the war were traitors to the working class and agents of the bourgeoisie inside the working-class movement.