Seems like you need to read up on civil war history then, and realize just how many civil wars are the result of the differences between the progressive and urban, and the rural backwater.
Basically every (attempted or successful) commie revolution pitted the urban population on the commie side, and the rural population on the fascist side. Sure, there was some overlap, but that was the main split. Funnily enough, in Asia this was the other way around.
Africa is riddled with conflicts between a largely urban elite on the one hand, and the rural peasantry on the other. Sure, Africa has a lot of ethnic strife as well, but they sure have their share of conflicts between various factions within a given ethnic group.
On a final note, it seems like you have completely abandoned your premise in the OP; this is no longer about culture or multiculture, now you are arguing in terms of race.
Your beef is not with multiculturalism, your beef is with multiracial countries.
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