This pretty much sums it up as in those regimes it was just politically motivated atheism not atheism motivated politics.
I think you are really missing the whole point here. It's not that communism=atheism or atheism=communism, it's the whole worldview that comes from the people who fought for and built communism. So, let us not call it communism, shall we instead call it I'll do it my way-ism. Or, we could even call it Republicanism, or Democracy. It's not the system,it's the people and their worldview behind the system.
Historical evidence is all over the map, but so far I think the Marxists have a commanding lead as far as sheer quantity of brutality, oppression, and body count (upwards of 100,000,000) are concerned. The fascist socialists are a distant 2nd, then we have imerialism 3rd, islamism a distant 4th, followed by the inquisition and witch trials and other evil "G-d told me you are bad" heretical evil-doing.
Nazi Germany was predominantly Christian and WW2 caused the deaths of 11.5 to 60 million people
“The total body count for the ninety years between 1917 and 2007 is approximately 148 million dead at the bloody hands of fifty-two atheists, three times more than all the human beings killed by war, civil war, and individual crime in the entire twentieth century combined. “The historical record of collective atheism is thus 182,716 times worse on an annual basis than Christianity’s worst and most infamous misdeed, the Spanish Inquisition. It is not only Stalin and Mao who were so murderously inclined, they were merely the worst of the whole Hell-bound lot. For every Pol Pot whose infamous name is still spoken with horror today, there was a Mengistu, a Bierut, and a Choibalsan, godless men whose names are now forgotten everywhere but in the lands they once ruled with a red hand. “Is a 58 percent chance that an atheist leader will murder a noticeable percentage of the population over which he rules sufficient evidence that atheism does, in fact, provide a systematic influence to do bad things? If that is not deemed to be conclusive, how about the fact that the average atheist crime against humanity is 18.3 million percent worse than the very worst depredation committed by Christians, even though atheists have had less than one-twentieth the number of opportunities with which to commit them. If one considers the statistically significant size of the historical atheist set and contrasts it with the fact that not one in a thousand religious leaders have committed similarly large-scale atrocities, it is impossible to conclude otherwise, even if we do not yet understand exactly why this should be the case. Once might be an accident, even twice could be coincidence, but fifty-two incidents in ninety years reeks of causation!”
Watt,When I say atheism, I mean atheists. You are technically write that ideas do not perform actions. People do. I was arguing that the logical of atheism if acted out by people have and will lead to mass murder, but technically you are correct. I should have said atheists not atheism, since an idea is not able to act. I was using atheism as a kind of short hand for atheism, people who are atheists and people who act according to the philosophical implications of atheism.
Watt,There are individual atheists who can be nice and even have the appearance of morality, but the ideology itself is rotten and leaves only corpses in its wake. I think the friendly ones have borrowed from Christianity as Nietzsche claims in the aforementioned letter. You seem like a bright and friendly interlocutor, what subjects in philosophy or theology would you like to discuses? I will start a separate thread to do so, if you like?