Many confuse A-Theist as Anti-Theist.
This is not the case. Its A-Theist in the same sense as A-Gender, meaning one that does not hold a theistic belief.
There are two types of Atheists:
Strong atheists are ones who claim not only they don't believe there is a God, rather they actively claim God does not exist.
This, of course has no validation what so ever as one cannot claim for absence of non-measurable concept.
The more common form of atheism (Dawkins, Claus, Hitchens and more) is simply the lack of belief (or acceptance) of the idea of a God (or any spiritual concept for that matter).
Don't confuse that with the idea that religion is dangerous. This has got no relation to being an Atheist or not.