No, it's not. It's a common opinion among white nationalists, but they are a tiny minority and they don't realize how different white people (or any ethnicity for that matter) actually are. If you put a bunch of British Columbians and Texans in a room, you might have ethnocentricity, but you won't have anything close to social cohesion.
This is a bad comparison. "White" is about as informative as "European" or "Indian". It conveys a vague notion of melanin levels and little else. Regions such as Europe or India are so diverse that a Finn and a Spaniard have very little in common. Same goes for a "Country" like India.
Someone from BC and someone from Texas actually have a lot in common - both are from immigrant societies and both speak the same language. Can't say that for someone from Kerala, India and Punjab, also in India.
Thats all fine, but we're talking about white nationalists...they're not exactly nuanced about culture. To white nationalists, whiteness is all that matters, and if we just kicked out all of the non-white people, we could participate in this enthocentric utopian fantasy that they have. Nevermind the fact that almost every ethnostate that has ever existed has had civil wars and irreconcilable differences. Hell, our own country is the result of some members of a homogenous ethnostate moving to get away from that state, and ultimately waging war against it.
Given the interminable arguments they have about "who counts as white" and their racial anxieties I'm sure they're more aware, on average, of the differences between a Texan, and a Californian, or a Scottsman and A Frenchman than those of us who focus on finding what we have in common and being good neighbors.
