I'm more interested in the cultures of feminity and of masculinity than in their potential biological causes. Men can be feminine (effeminate, sensitive, emotionally intelligent and open) in that respect too.
My point is there is this cultural part of the explanation of America's culture war. It's partly a war between toxic forms of both femininity and masculinity, as I argue below. I understand this isn't a politically correct hypothesis, but this factor seems pretty clear to me, and ignoring it wouldn't make it go away.