Do you really think that one's repulsion at a Nazi should be governed by the fact that Nazism is voluntary? That's not really the first thing I think of when I contemplate Nazis.

What if I'm repulsed by Republicans, or Tories? That's equally voluntary (if it is - some people's brains just seem wired that way), yet not being willing to kiss anyone who's a Tory might be seen as a mark of unreasonable prejudice.

What about smokers? That's certainly voluntary - a person may be driven by brain chemistry to crave tobacco, but it's always considered within the repertoire of reactions to refrain, or quit - yet many non-smokers find it viscerally repulsive in a physical way not comparable to the sort of dainty aversion that might describe one's distaste for romance with Tories, or even with Nazis. Is that, then, also a phobia or prejudice?

Of course there must be borderline cases, but I think there's a fairly reasonable distinction between being physically repulsed by transsexual women, and murdering them. If they're both "transphobia", we really, really need more words.