I think, among heterosexual men particularly, there's a lot of self-loathing for their own sexual desires, and it comes from a long cultural tradition of describing two very different things, one an act of violence and domination, the other an expression of mutual desire, as if they were the same thing, and defining it as central to masculinity.
It goes back much farther than Dworkin, of course, and it's one of the the things I blame the Roman Empire for.
