Yup, the melting pot idea is great while it lasts but it doesn’t last. Its like a cooling magma which slowly differentiates into mineral assemblages of like composition as it cools. With rocks though that is the end, with humans it is just the beginning of confilct and war.
I think the problem is that “melting pot” ceased being taught and instead the liberal “salad bowl” theory replaced it...which only divided us, of course.