Just so I can make everyone hate me, I’m going to grab a quote from Debunking Serano, over here. The quote I am going to respond to, which will put me firmly on the third side of everything again, is this:
[…] the assumption that the trans person’s gender is not authentic because it does not correlate with the sex they were assigned at birth. In making this assumption, cissexists attempt to create an artificial hierarchy. By insisteing that the trans person’s gender is “fake,” they attempt to validate their own gender as “real” or “natural.”
I work off the idea that yes, gender is an essential part of the self, something as invisible and as flavorful as personality. It changes your experience of your own life, but does not significantly change others’ experience of you; gender, like personality, is 99% inside your own head.
So, rejecting the premise that either gender or behavior can be feasibly conflated with genitalia at all, if there is a person out there who experiences their gender as correlating to any form of genitalia, that person’s gender is fake—entirely socially constructed.
Gender—as “gendered sex” or “sexed gender”—is entirely a social reality, which is not to suggest it’s not potent; just that, like “whiteness” and “blackness,” it actually has nothing to do with any kind of innate self. If you feel like you’re a “man” or a “woman,” that would be gender socialization, not just “gender.” There is an enormous difference between feeling that your body should be different and feeling that your gender matches a different sex. That’s utterly nonsensical; sex and gender have nothing to do with each other. The two are only conflated in the context of a sexed hierarchy, where gender is how you are socialized to act out your inferiority/superiority within that hierarchy.
Let me break this down into an innate situation: sex is not gender, and vice versa. Sex has nothing to do with behavior, same with gender. Society says that sex is gender, and vice versa, and that sex has everything to do with behavior, and so does gender. I do not say that, nor does any gender abolitionist I know.
There’s such a thing as a “sex identity.” It has to do with genitalia, and what you feel yours should be. It’s not the same as a gender identity. Internal gender has nothing to do with your behavior or genitalia; socialized gender does.
To suggest otherwise is to be “cissexist,” in the only coherent definition of the word I’ve found so far.