It's the year 2021. Why are people still racist?  We have occasion, over and over, to keep wondering. The Washington Post pondered the question during the Trump administration, when the 2017 Charlottesville uprising showed us that America's ugly KKK roots are still alive and well. Of course, the WaPo arrive at no answer, only a bald examination of the puzzle.  Racism, and all forms of bigotry, make no sense, and yet they seem to be hard-wired into our brains. In fact, recent years show that we divide ourselves along an increasing spectrum of arbitrary differences. Ageism has reared its head with the perpetual generation war. We just got through talking about how politically divided the "United" States is. We sit around in our idle time and make up more ways to divide us: rich vs. poor, dog people vs. cat people, whether or not we put pineapple on pizza.  People: Sort us into two groups, and we will find a reason to hate each other.      Since we will find endless reasons to hate each other,…