I think that the problem is that if you get three atheists together in a room, you're going to have at least five different opinions on any subject. While this is a good thing and a sign of an open mind, it doesn't really make for quality organization on a mass level.

We have nothing binding us together except for the fact that we disbelieve in the same thing and are fanatical in our opinion that bagels are superior to english muffins. While everyone likes to go on about how marginalized we are, we tend to be better educated and thus wealthier than average, so very few of us experience any real oppression whatsoever and there's no real motivation to give much more than lip service to fighting for our rights and equality, since we're rarely denied either.

As much as I like us as a group, I have to conclude that politically speaking, we're really just not much of a bloc to be reckonned with