IIRC, this hasn’t been debunked per se, but it was a very small, very limited study, and doesn’t really do a great job of explaining homophobia in a broader population. (I mean, you’re talking about 64 people in total; depending on your inclusion criteria, that could be a meaningless sample size.) Penile plethysmography is a proxy for sexual arousal; it’s useful in some instances–like predicting whether or not someone will commit more sexual offenses in the future–but isn’t even that great in those instances. If I remember correctly, there’s strong evidence that disgust is a trait strongly associated with conservatism, and homophobia is a an extreme disgust reaction.

FWIW, I was casually–but quite virulently–homophobic when I was younger. I’d been raised in a very conservative, evangelical religious group, and I believed all the bullshit that I’d heard about gay people. That changed once I lost religion, and actually met people that were gay. That, of course, is only anecdotal evidence, and does assume that I’m neither gay nor bisexual (and I don’t believe that I am), but it fits with what I’ve seen from conservative thought.

It depends on how you’re looking at homosexuality; are you looking at it as sexual attraction, or as behaviour? If you’re talking about behaviour, then a lot of that is certainly environmental, e.g., if you’re raise a non-permissive location, you’re much, much less likely to engage in homosexual behaviour. But if you’re talking about sexual attraction, then it seems very unlikely that it could be anything other than primarily genetic.

I think that the fact that there’s a difference between how people act, versus how people feel, is what confuses so many people about being straight, gay, bisexual, transgender, etc., and why conservatives feel like there’s a ‘gay agenda’ to make kids gay (or trans) when a permissive society allows more people to act freely on the way that they feel.

If you need to regularly scratch your anus, you probably have parasites. That’s one of the prime ways for some species of parasites (roundworms, I think?, probably tapeworms too?) to spread.

Uh, no?

Riots in France over unpopular political policies are so common that they’re a meme. Saudi Arabia overthrew it’s dictator via political violence. China, Russia, many others have had political violence on a massive scale.

Political violence is common. The only real difference is that–in theory–Americans have the tools to enforce regime change at home, should the citizenry choose to assert that ability. There are literally more guns than people (by a lot!) in the US, so our civil wars end up being some of the most bloody and brutal on the planet. (Roughly 2% of the entire US population died in battle in the US Civil War; US Civil War 2 would almost certainly be worse, since it wouldn’t be limited solely to direct military engagements.)