The physical things like food security and defence are absolute and cannot be overcome by opinion. The cultural basis for a nation state is partly real but partly artificially cultivated and far removed from people‘s real daily behaviour.

The nation state comes only from wanting it and then organising its existence, which involves doing so collectively with other states to overcome the physical constraints.

If you wanted to design states that could afford an insular mentality, you would have to ignore cultural boundaries to give them enough agricultural land, a large enough population for defence and easily defensible borders.

And supplies within their geographic footprint of all necessary raw materials…