What the hell is so difficult about a yes-and-no answer to the “trans women are women” question? For some, perhaps even most, purposes, yes, absolutely. For other purposes (women’s reproductive health, family policy, FGM), no.
This is no different from any other socially constructed group identity. Is Barack Obama African American? Yes. And no. Is the Nigerian immigrant who runs the pizza place near my job? Yes. And no. Is someone with a Jewish father a Jew? Yes. And no. Are messianic Jews Jewish? Yes. And no.
Am I a woman? Yes. And no. Even though I was identified female at birth and have gestated and lactated, there are ways in which I do not feel particularly comfortable being labeled “woman” and in which some people would classify me as not-a-woman. Being a woman is a social identity grounded in part, but only in part, on physical characteristics. It’s not a you-are-or-you-aren’t category.
(Disclosure: I too am a member of the frightening gender discussion group. Anyone who’s spent more than 5 minutes reading the group will note that there are many different opinions on gender and trans gender issues held by members of the group. I’ve learned a lot and been challenged to think of better arguments as a result of participating in the group. I’ve found myself agreeing and arguing with Hungerford in different threads on different topics. Gender is not an easy thing to define or analyze, and if we’re going to discard every single writer or forum with whom we don’t completely agree, we’re going to end up putting feminist intellectual history through its own extinction event.)