Progressives like to say ‘vagina, vagina, vagina’, both because it is supposed to be the essential thing about femininity, and because conservatives are vaguely uncomfortable about it.
I’ll believe a transwoman about being a transwoman when xe gets a uterus transplant, carries and child, and becomes a mother. But mothering behavior is partly instinctual, and there is as yet no clear indication of how it works, so we must remain suspicious then.
The essential body part that makes a woman a woman is the uterus. Not the ovaries, that make salmon females, but the uterus that is the symbol of the massive investment female mammals put into their children. Many mammals go on to spend up to a year training the children that already took several months to develop inside them. Humans, of course, spend a decade or two.
Since the very first communist philosophers, communists have suggested that men or men and women should not know their own children but each should feel family ties to all. Good luck with that, commies.
When a communist starts going all ‘vagina vagina vagina’, take some time to reply ‘uterus motherhood lifecycle’; because nothing scares commies more than the idea that humans also have a lifecycle, 80 years is a long but finite time, and the period of their life in which they can reproduce is also longer than many generations of other mammals but still finite.