Atheists are a diverse bunch of people. There's no single set of beliefs or ideas that unite all atheists under a single banner. In fact, the only thing they have in common is that they don't believe in any deities.
This can make understanding the atheist community rather difficult for an outsider. Doesn't it make more sense to unite with people based on shared beliefs or identifying by what you are rather than what you are not? After all, it makes sense to start a golfing club, but there's no point in starting a club for non-golfers. Why should non-believers be any different?
The atheist community is important because religion is not like golf. In a logical world, atheism would be the de facto status, a status quo requiring no labels, organizations or movements. Religion, like a hobby, would be an added identity for people who chose to affiliate with any given religion. But that's not how religion works.
What if Golf Was Like Religion?
Imagine that a golfer, Frank, is very passionate about his golfing. It's changed his life, giving him purpose and inner peace. Eager to share this wonderful message with the rest of the world, he decides that everyone on the planet should be a golfer. To complete this end, he starts sending out emails to all of his friends and colleagues, outlining a plan to make golfing the official international pastime.
Frank doesn't stop there, though. As his following starts to pick up members, they start drafting legislation that will protect golfers and give them certain benefits, including freedom from taxes. Golfers would also get special holidays celebrating the invention of the sport or the first ever golf T, and they would be exempt from working on these special days. Eventually, they manage to hold enough large fundraisers to build support among lobbyists for their plans.
At this point, golfers are still a very small minority in the world. Many other people prefer tennis or go swimming, and some people have no interest in sport activities at all. Nevertheless, through their political power and loud voices, the golfers have secured their sport as the de facto official sport.
The golfers insist that everyone begin to wear cleated shoes, plaid shirts and other golfing attire. They also want to make sure that children learn golfing skills at an early age, so they change the curriculum so that golf becomes the only sport they're taught. Golfers become disgusted with non-golfers and look down on them.
In this situation, it makes good sense for the non-golfers to unite against this kind of prejudice. The non-golfers may have different goals from each other. Some might be primarily interested in changing the golf-based curriculum in schools. Others will reach out to the non-golfers who are being oppressed in areas where the enforcement method of golfing is particularly cruel. A few might hold rallies, create art that shows the arbitrariness of golf obsession or simply announce publicly, "I am not a golfer." If there are enough of these non-golfers, they might even start up their own website and Facebook community to hold discussions about the problems of being a non-golfer in a world filled with loud, pushy golf enthusiasts.
The Power of Community
In an ideal world, people could always identify by what they are rather than what they are not. Until religion stops dominating the public sphere, however, atheists will have ample cause to unite for their rights. Religions put pressure on individuals, governments, the legal system and educational institutions; without the non-religious pushing for advocacy and support, the public sector can be easily steamrolled by a religious agenda.
Our lack of belief is more than disbelief; it's a way for us to find each other and rally around our shared values. Not every atheist cares about worldwide religious injustice and oppression, but many atheists do, and uniting under banners such as Atheist Nexus, American Atheists or Atheist Republic gives us the strength to combat these injustices head-on.