Failure to accept gods is no more a leap of faith than is doubting the existence of the Loch Ness Monster, Bigfoot, or Santa Claus. It’s not “faith” when you refuse to accept a proposition for which there’s no evidence.
In general I agree with Oluo’s thesis that atheism usually jibes with a liberal outlook. Many conservative political views derive at bottom from religion. And there’s a lot of evidence that religion is often an outgrowth of social injustice: the heart of a heartless world. Ergo, if you’re an antitheist and want to work towards the abolition of faith, one way to do that is to improve the lives of the impoverished and dispossessed.
But not all atheists are antitheists, and not all of them accept the connection between social well-being and nonbelief. Atheism is simply the refusal to accept supernatural deities, and there are plenty of conservative atheists. The view that this life is all we have, and that we should help our fellow creatures, is not atheism but humanism.