Next time a faithful person accuses you of being a "communist" because Stalin allegedly was also an atheist, show him or her this website: http://www.evilbible.com/hitler_was_christian.htm
Adolph Hitler was a devout Catholic who blamed Jews for the death of Jesus. Does that mean all Christians are nazis?
Of course they will say "No! Hitler was crazy! That doesn't count!".
Well, Stalin was also crazy, wasn't he? I am told Stalin also had a mustache. Does that make every mustached man a communist? These false correlations are meaningless.
Atheism has nothing to do with communism.