Does Atheism Entail any Political Philosophies?:
Atheists can be as political as theists but also like theists, atheists political beliefs and ideas are diverse. It's sadly common for anti-atheists to assume atheists necessarily hold particular positions, such as that they are all liberal or all communists. The truth, however, is that you can find atheists in all political philosophies as the absence of belief in gods, atheism doesn't entail or exclude any political philosophies except those that require theism.
Atheists & Liberalism:
It's true that you'll probably find more liberal than non-liberal atheists. Atheism represents a challenge to or dissent from traditional beliefs and traditional religion. Liberalism, through most of Western history, has also challenged traditions and traditional ways of doing things. Liberalism has furthermore generally done more to promote the rights of various minority groups something which atheists obviously benefit from, given how much discrimination they tend to encounter.
Atheists & Conservatism:
Atheism among conservatives is unusual, but not unheard of. Conservatism seeks to "conserve" traditional values and ways of doing things; atheism, however, challenges or rejects many traditions. Theistic religion is, moreover, a sort of repository for traditions in the West and if atheists don't accept such religions, upon what can they base their conservatism? It's not impossible, but it's more difficult than for many theists and presents a real challenge.
Atheists & Libertarianism:
More common among atheists than conservatism, but probably less common than liberalism, is libertarianism. Libertarian political philosophy advocates more limited government roles in all aspects of society than either liberalism or conservatism, something which isn't difficult for an atheist to accept. It's common, but not necessary, for atheists who adopt libertarianism as a political philosophy to also adopt Objecivism as an overall philosophy of life.
Atheists & Communism:
Although the common accusation that atheism is necessarily associated with communism is untrue, it is true that many or most communists are atheists. It's possible to adopt communism without also being an atheist, but that's not the case with most. This is probably related not only to the anti-religious
writings of the founders of communism, but also the degree to which religious institutions have typically defended the social and economic status quo
in capitalist societies.
Atheists & Fascism:
I have no data on atheists who have adopted any forms of fascism, but there's nothing about fascism which would necessarily exclude people who don't believe in any gods. It's likely that being fascist would be challenging for an atheist because, like conservatism, fascism relies heavily on traditional symbols and myths which are often religious or connected to religion. Anyone who doesn't accept these symbols and myths would have trouble reconciling themselves to fascist politics.
Atheists & Anarchism:
Like libertarians, anarchists want to reduce the size of government drastically so drastically, in fact, that it would be ideal to have no government at all, or at least nothing beyond small community councils. Anarchist political philosophy may be associated with extreme libertarianism, extreme communism, or other ideas all of which are compatible with the absence of belief in gods. Indeed, the belief that there is no god to "rule" over us has led to some reject human rulers as well.
Atheists & Monarchism:
Monarchist political philosophy, the belief that we should have kings and queens as the sovereign leaders of government, is quite rare in the modern era but it hasn't died out completely. There are still a few monarchists out there and there's nothing contradictory about an atheist adopting monarchism. It's not going to be easy, though, since monarchism typically incorporates religion as a basis for claims to sovereignty; so among the very few monarchists there will be few atheists.
Atheists & Political Apathy:
Political apathy among atheists is probably about as common as it is in the general population. There's nothing about atheism which would prevent a person from simply not caring who gets elected or what the government does. Given atheists' minority status and the discrimination among atheists, though, it's possible that political awareness among atheists is a little higher than average but it need not be.
Atheists & Political Issues:
As atheists become more vocal about who they are and what they believe, we'll see more atheists taking stands on a variety of political issues. It's likely that we'll see most atheists adopting and promoting positions consistent with liberal politics, but we'll also see atheists taking diverse stands all across the political spectrum. Even among atheists who would describe themselves as liberal, there will be disagreements on particular political issues, agendas, and policies.
As with the wider community, this diversity is a sign of strength, not weakness. There can never be a political party based solely around atheism because atheists disagree on too many issues and that's a good thing. Atheists would have much less to offer society if atheism were narrow ideology with a defined dogma that all had to adopt in order to be considered atheists.
If atheists are going to have a broad impact on politics and society, it's not going to be through standing outside social and political institutions, trying to chip away at the edges. Instead, it will be by working within those institutions, as normal members who simply happen to be atheists. This may be one reason why the presence of atheists causes suspicion and fear: by working within groups or institutions yet refusing to keep their atheism quiet, atheists may slowly transform their surroundings in ways difficult to imagine for those accustomed to environments where religion and theism are privileged.
For this to work, atheists must align their personal interests and their interests as atheists with the common good. What this means is that, for example, the struggle to gain equality and acceptance should not be merely as atheists, but also as human beings, ensuring that other minorities will also benefit. The struggle for equality has always been a struggle against the privileges of some groups over others, so atheists should strive to ensure that they don't create or justify forms of privilege themselves.