To those who are saying 'What does it matter if a tyrant is left or right' - I agree, but it depends on who you are.
Left wing and right wing regimes have very different enemies. Stalin targeted the rich, the aristocrats, the land owners and investors. Those groups all benefitted under Hitler's rule.
Hitler targeted racial minorities and outsiders - groups who occasionally benefited under the rule of outsiders like Stalin, Caucescu or Milosevic.
"We The Living" Ayn Rand. Communism displaced the Rich and Powerful with Party Loyalists. They just moved right in.