Of course, he was one of the most vicious anti-semites breathing at the time. A guy who made Wagner look warm and loving.
It could be said that Vladimir Lenin born in 1870, helped to birth the totalitarian side of Marxism.
The split on the Marxist Left was about whether democracy could advance political and social reform without revolution.
Social Democrats insisted capitalism could be tamed. The Communists held only a through transformation could produce a socialist society.
We know the outcome of that debate and I don’t think even Marxists think man is still perfectible.
Socialism was never going to lead to the classless utopia people imagined would be the end result.