Communism is globalism, as they are anti-national identity. Nazism was based in the belief that Germans were the ubermenschen. Overlords, if you will. The remainder were considered sub-human, or Untermenschen. Communism takes everyone under their big iron umbrella. You can't get out.

There's other differences, such as a corporate merge with the state with fascism instead of full blown destruction of industry with communism.