–“(Correct me if I’m wrong) did the ‘new & improved’ modern American Constitution proposed require an ethnostate or no?”—
Short answer is yes. Long answer is that it creates the possibility for self-determination by self-determined means, and specifically for ethnostates, which I assume is what would be the driving force for separation and reformation. However, since we must accept the geostrategic necessity of preserving the territorial integrity of North America under a single military and trade system, it allows for the formation of various city-states and states with different preferences. In other words, we convert the ‘leftwing’ cities into city-states, and isolate them from infecting the rest of the country.