- Religious or cultural indoctrination
- Thinking gay sex is gross
- A fear that a gay guy is going to come on to them and violate their precious heterosexual butthole (this fear is unique to men and is usually totally unfounded - the men most paranoid about this tend to be completely unattractive to gay men)
- A fear (in men again) that they will be seen as gay if they aren't homophobic
- Repression of actual gay feelings (seriously, look up the studies - most aggressively homophobic men are closet cases)
Homophobia can have funny effects on men's behaviour. The dominant stereotype is that gay=effeminate so to distance themselves from any potential gayness, many men get obsessive about being "manly". It seems like a good theory but the insistence on surrounding yourself with other many men and performing acts of physical prowess can't help but, well, seem a little gay. I find it funny how often homophobia and homoeroticism cross paths. In Australia particularly this can get extreme. One of my favourite jokes is "An Australian male's definition of a poofter is anyone who likes women more than beer".
I'm continually being called gay on YouTube for example because, by mainstream standards for men, I'm expressive (particularly with my hands) as well as articulate and well-spoken. People (usually males) tend to say it because they think, according to the stereotype, it might be true and/or they think it's an insult. I fail to see how the topic can be of any relevance to anyone, male or female, straight or gay, unless they want to suck my dick. People interested in sucking my dick may feel free to contact me privately.
There are many good jokes about the boundaries between male camaraderie and homosexuality, a favourite of mine can be found online - the trailer for a fictional film that combines sequences from "Back to the Future" with the themes of "Brokeback Mountain". In "Brokeback to the Future" we learn the truth of the relationship between Doc and Marty. It's a beautiful story. What I find really funny is that they could create the gay mood just by using images and dialogue that already existed in the original movie.
More recently, someone tried to do the same thing with the movie "300" with far less success. It fails for two main reasons (1) it simply isn't as well-done as "Brokeback to the Future" (although some of the editing is good) and (2) you're trying to find "hidden" homoerotic subtext in a film about near-nude Spartans? Ummm, guys, how good is your knowledge of history?
What I found far funnier than the video was some of the comments it inspired. 300 has been very popular with young men. And many young men are desperate to assert that they are not gay. Homophobic reasoning often follows this path: "if I like something gay or admire someone who's gay, that might mean I'm gay. Therefore I don't like anyone who's gay and nothing I like is gay." This train of thought came out pretty strongly in some of the comments like:
"show some repect to the spartans you idiot ... the Athenians were into sodomization with their pages, not Spartans ... Too hard to make spartans look gay ... Dumbb video. you CANNOT make 300 seems gay (grammatical errors are in the original) ... actually spartans looked down upon homosexuality ... spartans were straight, athenians were gay ... just doesn't work with this movie ... i dont think that 300 guys that have KIDS and like to kill people are going to be gay."
Boys, boys, boys. I think all homophobia is stupid. If you're going to try and justify your homophobia, you might want to avoid making yourself even more stupid by making idiotic assertions that fly in the face of all current historical that I'm aware of. When you thrash around like this, tying yourself in knots saying "NOTGAYNOTGAYNOTGAYNOTGAY", honestly, it just looks like you're trying to hide something.