From Feminist Critics:
Feminists, do not focus upon male rape generally, or male prison rape in particular. This is unsurprising, and not, in itself, particularly problematic.
What is problematic with feminist discourse about male rape is not that they don’t discuss it at all – clearly they do – or that they don’t discuss it enough. The problem is that they anomalise it, that is to say, they treat it as some kind of anomalous variant of rape which, according to them, is something which normally happens to women. The latter is simply “rape”. Rape that happens to men in prison is “prison rape”. Rape that happens to men outside of prison is “male rape”. The word “female” is sometimes used as an adjective with “rape” to contrast it with male rape, but “female rape” is not used by feminists as a category designation in and of itself. It’s just “rape”. “Male rape” and “prison rape” sometimes get their own threads, effectively discoursive ghettos. But they are often excluded from threads about “rape”.
If rape that happens to women is “rape”, it follow that “rape” is something which happens to women. This equivalence is reinforced by the interchangeability in feminist (and, due to its influence, in mainstream) discourse between the ostensibly gender-neutral (but implicitly gendered) functional category “rape” and the explicit gender category “violence against women”. The overall effect is to render male rape invisible outside of the ghetto.
What the ghetto threads do is give the appearance of addressing these issues positively, while ensuring that male sexual victimisation remains a marginalised topic. Since male victims are already marginalised to the point of invisibility within mainstream society, the effect is to preserve and extend gender inequality contrary to feminism’s stated aim.
Read more here.