Well, as you say this (3 year old!) discussion is in danger of going off track, and an Everton forum probably isn't the best place for it, but keeping it short, of course terrible things have been done by atheists, but I think it's fair to say that you'd struggle to point to any atrocities from history committed in the name of atheism. And I think it would also be fair to say that you can't say the same about religion.
Also, I have read a lot of history thank you, and that is exactly what happened to Galileo...no real need for condescension there