Not likely. Why would the groups subject to this effect be defined at the relatively artificial level of the nation state, and not at any other subnational (sta

Not likely. Why would the groups subject to this effect be defined at the relatively artificial level of the nation state, and not at any other subnational (states or provinces) or supranational (EU or cultural sphere) level? Furthermore, watch out for confirmation bias: why is Japan a possible exception rather than a counterexample?