Those who stand for the “neither-victory-nor-defeat” slogan are in fact on the side of the bourgeoisie and the opportunists, for they do not believe in the possibility of inter national revolutionary action by the working class against their own governments, and do not wish to help develop such action, which, though undoubtedly difficult, is the only task worthy of a proletarian, the only socialist task.

V.I. Lenin, “The Defeat of One’s Own Government in the Imperialist War” 

Via Marx Engels Lenin Institute