Who said anything about forced integration? You suggested the idea of nationality was silly. If the idea of nationality has no salience, then there is no meaning to national identity and therefore integrating yourself into any other human civilization should be completely seamless.
If we use the reverse of your logic, then being a national of X country means you should be able to integrate within any subcultures within that nation entirely seamlessly.
For example, you should be able to walk into any Native American tribe and be able to seamlessly integrate yourself into their culture despite having zero background.
Not really. In a whole number of ways. I actually have no idea how you can say this with any honesty.
I mean, are you really arguing that national identity is the major stumbling block in integrating to a tribe in Papua New Guinea.... Here's a hint: Other :tribes: would have difficulty integrating, and they've likely never been introduced to the concept.
Please explain to me how you're so confident while simultaneously so widely and clearly wrong.