Sorry for assuming you were European in expressing what I see as ironic. Perhaps itself ironic as a mistake. My bad.

I think Europe and the Americas are differently heterogeneous and differently homogeneous. Certainly the Europeans have made more practical strides in building a coalition across their members than, say, South America or Central America. The reality is that Europe demonstrates a higher degree of solidarity between states than these other places. So it's strange to me to argue the opposite.

But if I understand, your assertion is that the Mayans, the islanders of the Caribbean, the people of Peru, or the Amazonians are less culturally different from one another than the citizens of, say, Greece and Norway? I'm not sure I buy it personally .. but I can see your argument.