“Every country has their share of ethnic or cultural or religious groups.”
The key is who defines such “groups”. It used to be there were Irish, Frenchmen, Germans, Poles, Jews, Spaniards, etc. Now they are all grouped into white.
I’d venture a guess that people who are not in a group define all the other groups in order to create a group of their own. Or, if that is incorrect, then each group defines all the other groups how they see fit by majority vote.
Do I get an E for effort?