— Wilhelm Liebknecht
Context: The internationality of socialism is a fact that is daily becoming more evident and more significant. We socialists are one nation to ourselves, – one and the same international nation in all the lands of the earth. And the capitalists with their agents, instruments and dupes are likewise an international nation, so that we can truthfully say, there are to-day only two great nations in all lands that battle with each other in the great class struggle, which is the new revolution – a class struggle on one side of which stands the proletariat, representing socialism, and on the other the bourgeoisie, representing capitalism. While the bourgeois world of capitalism continues and the bourgeoisie rules, so long are all states necessarily class states, and all governments class governments, serving the purposes and interests of the ruling class, and destined to lead the class struggle for the bourgeoisie against the proletariat – for capitalism against socialism, for our enemies and against us. From the standpoint of the class struggle which is the foundation of militant socialism, that is a truth which has been raised by the logic of thought and of facts beyond the possibility of a doubt. A socialist who goes into a bourgeois government, either goes over to the enemy or else puts himself in the power of the enemy. In any case the socialist who becomes a member of a bourgeois government separates himself from us, the militant socialists. He may claim to be a socialist but he is no longer such. He may be convinced of his own sincerity, but in that case he has not comprehended the nature of the class struggle – does not understand that the class struggle is the basis of socialism.