Not that long ago, Bill Clinton was half-jokingly hailed as “the first black president” because he was cool, a liberal and could play the saxophone, a bit. If Clinton tried that today, he’d probably be impeached for “cultural appropriation”. That’s because the phenomenon of progressive identity politics, which is sweeping across western civilization like a plague, is herding people into tribal associations based on skin colour, gender, ethnicity and other biological and cultural characteristics. Humans have gone down this road before, writes Mark Milke, and it always ends badly. We’ll do much better if we get back to celebrating, tolerating, and borrowing ideas from other cultures.