You're on to one of the biggest controversies of all: were all the big things that happened (an almost infinite list of almost infinite badness) due to Stalin,

You're on to one of the biggest controversies of all: were all the big things that happened (an almost infinite list of almost infinite badness) due to Stalin, or was it Lenin, or did it all go bad starting with Marx? Or the French Revolution? Much ink and much blood spilled over those questions. Animal Farm touches on it (Orwell was a socialist but hated Stalin). Solzhenitsyn came to the opposite conclusion: that the Gulag and the purges started with Lenin. I don't think it will ever be settled.