I would think Pol Pot, Hitler, and Stalin would fit into the capital-A Atheist group you're discussing
Below is my standard response to this idea, although I originally wrote it to someone who was claiming this idea as hard truth, which you are not, so it may sound a bit harsh. BTW, I was responding to the Big A atheists as a hypothetical idea. I do not believe atheism is the root of any problem.
Equivocating non-belief in God with committing heinous acts is a blatant duplicity and no intelligent person here is going to tolerate it.
We have said it, over and over and over in many threads. Pick any name from that list, any example, and ask yourself. Was the problem here that these people were being too rational?
Lets take Jim Jones. Did this atrocity occur because Jim and his followers applied too much critical thought? Did they demand too much evidence and were too consistent in their logic? Was the problem that they wanted things to make too much sense?
Lets take Kim Jong. Is the problem with this situation that he and his people apply too much analysis? Are they being too careful in their thinking and being too reasonable in their actions? Are they too concerned with being conscientious and precise?
Lets take Jeffrey Dahmer. Was his rape, murder and cannibalistic acts a result of being too focused on legitimacy? Was he requiring too much validation and keeping his thoughts too organized? Was he too involved with accuracy and fastidious inquiry?
Do I need to go through the entire list? Skepticism is essentially what every atheist here is promoting. We advocate applying critical examination to the claim of a deity. Is this what lead Alfred Kinsey to exploit children for sex?
The atheist posters in this sub forum are simply promoting rational skepticism. We are trying to discourage dogmatic adherence to an ideology, which was the engine of Hitlers reign. Knowing that we do not believe in God tells you nothing about what we do believe in or what our intentions are.
Religion has been defended in 3 ways in this thread.
Religion is true - We've shown that can't be proven or even supported.
Religion does good things - We've shown nothing good religion provides is unique to religion itself, although the potential evil religion holds is indeed unique and all too easy to unleash.
Atheism leads to bad things - As stated, we are promoting skepticism. Atheism is a term vested on us by theists. The same thing we can find wrong with atheistic regimes are the same things we find wrong with religious regimes; dogmatic adherence. Rational thinking, evidential accountability, and enlightened attitudes helped us overcome fascist and communist dogmas. We should let these forces of sophistication eradicate religious dogma as well.