I'd like to offer some advice to make things go a bit more smoothly. There's a widespread view that all beliefs are political, you can't be apolitical, and anyone arguing for a belief opposing yours must be an enemy. To me, that view is pretty much a type error. Beliefs are value-neutral. Only arguments for or against beliefs can be political or not.
More specifically, some arguments are rational (based on evidence) while other arguments are political (based on who benefits and who loses). You can be a very civil person, but still reach for political arguments when defending your beliefs, and thus cause net harm. Or you can be a rude person, but drawn to arguing based on evidence, and thus cause net benefit. It's up to you.
Now go forth and make a flamewar :-)
So if people choose to believe in something because that has certain consequences - then a belief can be political.
EDIT: To expand on this a little... It seems to me that you divorce a belief itself from its consequences. As there are a lot of beliefs that have immediate and direct political and social consequences, i think that this separation is questionable.
If you have a belief, you probably will act on that belief. Having a belief and _not_ acting on it _at all_ seems rather useless and abstract to me. I'm not saying that this doesn't happen, but in general, if some person has a belief, he (or she) will act on that belief.
So, to be blunt: for some beliefs, having them is a political act.
For example, my decision whether to take an umbrella today must be based on my honest best guess whether it'll rain today (and the relative utilities of various outcomes). If I shift my best guess one inch away from what's warranted by evidence, to obey social pressure or something, then acting-as-if the new belief was true will predictably lead to lower expected utility for me. That holds always, no matter how controversial the belief.
When social pressure is weak, it mostly makes people lie about their beliefs, while still acting-as-if their best guess was true. When social pressure gets strong, people start acting-as-if false things were true, and get lower utility. No amount of pressure can change the fact that actions based on accurate beliefs lead to higher expected utility. That's why I'm not a fan of social pressure on beliefs. For both individuals and societies, the best consequences are achieved by believing what is true.
Two minor points:
1) What is truth? How do you know whether something is true? By perceiving it? Is your perception not influenced by belief?
I'm not saying that we cannot know truth, ever. But we have to keep in mind we might be wrong, too...
2) Believing in something might _make_ it become true. Or, to put it differently: Belief may lead to actions which change reality - essentially a self-fulfilling prophecy.