" What you can’t argue is that this somehow makes ethnocentrism in the political environment of a nation state “natural,” as the concept of the nation and the state have been aligned for hundreds of years now."
??? Yes, I'm making that argument and it's really obvious.
The 'modern nation state' is not fundamentally different from historical 'states' in this regard.
'Gaul' was an administrative state, part of the Roman Empire, roughly ethnocentric. 'France' is now.
Borders bounce around, but they mostly fit between ethnic groups. It doesn't really matter whether we are dealing with the modern notion of state or not.
"Some more so than others. The US, no, Sweden, mostly.
But this distinction basically proves this is not intrinsic to how humans function."
It really doesn't.
That 'some nation states' do not form along ethnic boundaries in not way 'proves' that ethnicity is not a natural vector for state formation.
Even if 'most' nation states formed along some other means, it still wouldn't prove that ethnicity is not a vector of formation.
The fact a number of ethnocentric states exists proves that it's a vector of formation.
The fact that 'most states' are roughly ethnocentric proves my point.
It's fairly obvious and not very controversial.
I think it's just one of those issues that triggers some people who hate the fact that ethnicity is a fairly important part of our identity, and then they step out of their ability to apply rhetoric in a reasonable way i.e. a kind of bad faith argumentation. It's the only explanation I can fathom for why people would argue with something so obvious. Vietnam has Vietnamese and Korea has Koreans. Obviously it's more complicated than that, but unless there are literal Nazis running around, and there generally are not, then who cares. It's really not a problem in most places in the world.