Possibly the most important part of the mental model humans construct is their mental model of themselves. This is what we call our identity. It takes all the beliefs we have about ourselves and attempts to put them together into an internally coherent whole. Some of our most cherished political, religious, racial, and gender thoughts about ourselves tells us who we are and how we ought to interact with the world.
Mary Eberstadt has a new book called Primal Screams: How the Sexual Revolution Created Identity Politics where she makes the case that the 1960s sexual revolution is what gave rise to identity politics today. I think, while that may have played a part, the identity politics craze can’t be completely laid at the feet of the sexual revolution.