I assume that by “share the same culture” the author meant things like language, value systems, religion, inherited biases, and views on the scope and purpose o

I assume that by “share the same culture” the author meant things like language, value systems, religion, inherited biases, and views on the scope and purpose of government. Within these categories, there’s a range of tolerance levels from “I love my neighbors and would sacrifice my well being for theirs” to “I’m OK with my neighbors but don’t feel any sense of group attachment,” all the way down to mass riots and civil war.