I think it was VirginiaTam who said:

Religions can't prove God exists and atheism can't prove God doesn't exist.

You miss the point, VT. Atheists (such as me) don't need to prove that god doesn't exist. They merely make their own decision, "I believe no god exists," or perhaps the lesser statement, "I don't believe a god exists." To paraphrase Jefferson, that steals no-one's purse and breaks no-one's leg. (Thanks, RangerSteve)

If a person calling himself an atheist arrogates to himself the right to protest Obama's use of "So help me God" in the inaugural oath, that person is not acting as an atheist as such, but as a controlling busybody who happens to include in his belief system the tenet that there is (or maybe "should be") no god.

Dave Oesterreich