Q, if as you said all people are the same in all places (same capabilities, not necessarily the same in their hearts/deeds), then atheists are no exception.
The only reason we have no history to back anything up about atheists when they are in the majority is that they have never been in the majority (exception of Stalin... sweep it away as you might like... not a good example for atheism as a majority in charge). But I would state that when religion is placed into the hands of politicians to wield and enforce their chosen ideology, then you get what we have had in the exact same way as Stalin. Politics USING the faith of people and turning it to their own end.
You can change the words around, but if people are people as you say, then the same people who want to hate others for being different (for believing) will simply be people who are atheists hating others for being different (having faith). You think atheists won't form a movement and seek to destroy people of faith? Who knows? But it is EASY for something like that to happen. Just create the fear of believers, make them into a threat. And many believers in religion (such as with Stalin) make that fear and that threat pretty easy to instill in others. Especially when they are creating wars over their different religions. Easy to see people standing up and saying "Enough... all of you are finished." Regardless of whether or not that has been justified or if any crime has been committed. Some already do that in their minds as it is. Makes no sense to me why some find annoying, the people of faith who are 'live and let live' and who would never want your rights to be intruded upon. So yeah, I can see the same thing happening, same rights being trampled upon, if someone like Dawkins was in charge... or in the majority. Not all at once. Little by little.
And Q... if you believe in a god, even just one... you are not an atheist. That is another pet phrase of Dawkins' isn't it?
Peace,
tammy