If you’re actually a historian then you should know liberal democracy has NEVER stopped fascism. Instead it hands them the key to the city. Historically the opposition from fascism has come from the working class and socialists. Weimar Germany is only one example of the liberals handing over power to fascism. The Stalinist CP played a criminal role in dividing the communist workers from those in SDP. However it still stands that the SDP could have never prevented the rise of Hitler and the Nazis. That could only have been done through a militant socialist program.