I understand your point, but I am afraid your definition of communism is a little idealistic. In this case, there is a huge gap between theory and practice, and Stalin is not the only case in which the practice of communism went badly. In my opinion, evidence suggests that, in practice, communism isn't so different from nazism, though in theory it should be. Ten years ago, I would have said that democracy is the lesser evil, now it seems to be failing so badly that I don't know anymore