So what's the difference between sex and gender, then? Are we talking gonadal vs. hormonal? Hormonal vs. genetic?
Note also my emphasis on gender identity rather than "gender" (I do so for the very reason that "sex" and "gender" are typically used interchangeably). When we are talking pronouns and gender roles within society (which we are since the original post discusses political ideologies), then we are talking identity, which is socially constructed. It may have biology as a basis, but once we discuss roles and pronouns we are in the realm of sociology.
Tell me, how do you know what gender someone walking down the street is?