Note the misspelling of "atheism" in the graphic here. That just drives me nuts. But the rest of it is interesting.
I don't know if this explanation is true or not, but I've often wondered why religious believers hate and fear atheists so much more than they do theists who disagree with them.
I mean, why should my disagreement be so alarming, when believing in different gods entirely - and not yours - isn't? (Not to say that many people don't hate those other believers, too, but the hatred of atheists is just unmatched.)
I always figured it was because atheism threatens them as an actual possibility. I mean, the typical theist isn't going to be tempted by some other religion than the one he was raised to believe. Sure, converts happen, but they're very, very rare.
You're a Christian because you were raised Christian. If you'd been raised Muslim, you'd believe in Islam. If you'd been raised Hindu, you'd be a Hindu now. But you're certainly not going to be tempted by any of those religions now. How silly would that be?
Usually, you don't even have to think about it. As a Christian, you might ask an atheist if he doesn't fear Hell - the Christian Hell, of course - but you yourself don't lay awake at night worrying about the Islamic Hell. Of course not! After all, you weren't raised Muslim.
Atheism, on the other hand, is an actual option. You see it as a threat, because it does threaten your beliefs, while other religions don't. Theists tend to be scared to death of atheism because there's a real, non-zero chance that they might become atheists, themselves.
In a way, I always thought it was similar to how virulent homophobes have so frequently been caught engaging in homosexual acts themselves. Their hatred and fear of homosexuality came from the very real threat it posed to them.
For people like me, on the other hand, it's quite different. I can't imagine why gay marriage would affect me in the slightest. No matter how welcoming society becomes for gay people, I'm not going to be tempted to form a homosexual relationship, because I feel absolutely no sexual attraction for men. Thus, I don't feel threatened by it.
I made the title of this post a question, because I don't know if this is the right answer - or even part of the answer - or not. One study certainly doesn't settle anything. It seems plausible, but then, I think my own explanation seems plausible, too.
Maybe they're both right. Or maybe neither is. I don't know.
Edit: PZ Myers has posted several reasons why that video annoys him, most of which back up my own doubts (though explained better). He also says:
For being the “most despised and distrusted group in America”, we do fairly well. Atheists tend to be better educated and a bit more well off than many believers; I can walk down an upscale suburban street and not get hassled by the police or shot. Ask a black atheist or a woman atheist which aspect of their identity is most likely to get them discriminated against, and it usually won’t be their atheism.
So back off on the persecution theme, already. Leave that to the Christians.
Good point. Indeed, all of the points he makes there are good. Nevertheless, it is true that atheists poll very, very badly in America, far below most other groups of people.
I don't feel 'persecuted' by that. As far as I can tell, I've never been discriminated against because I'm an atheist. Then again, no one can tell I'm an atheist just by looking at me, and the subject rarely comes up in conversation. Still, even when people do find out I'm an atheist, they don't seem to treat me any differently than they always have.
Of course, those people already know me. Would they hire a stranger if they knew he was an atheist? Would they vote for a politician if they knew he was an atheist? Atheists have the huge advantage that we look just like everyone else. And it's very, very easy to stay in the closet.
But it's still true that theists tend to hate and fear atheists - although most of them have probably never even met an atheist, as far as they know - more than other people they disagree with. I'm not convinced it's because we remind them of death (I'd need better evidence before accepting that explanation), but it's still an interesting question, even if I don't feel like a victim.