I used to have this kid as a colleague (he was 17 at the time), who had been primed by his parents to be a nationalist.
One of the times, he was completely bewildered by my stance was when I said that even if I cared about having things in common with other humans, I feel like I have more in common with the folks just across the border than those who live several hundred kilometers away within the same border.
You could really see the cogs in his brain churning, trying to grok how you can have things in common with team B, when you've been assigned to team A.
All the contententious debates like these start to fall apart when you think about it too much and realize that these problems only exist because some idiots a few centuries ago made some selfish decisions and we keep insisting on perpetuating them
Not like the brazen giant of Greek fame,
With conquering limbs astride from land to land;
Here at our sea-washed, sunset gates shall stand
A mighty woman with a torch, whose flame
Is the imprisoned lightning, and her name
Mother of Exiles. From her beacon-hand
Glows world-wide welcome; her mild eyes command
The air-bridged harbor that twin cities frame.
"Keep, ancient lands, your storied pomp!" cries she
With silent lips. "Give me your tired, your poor,
Your huddled masses yearning to breathe free,
The wretched refuse of your teeming shore.
Send these, the homeless, tempest-tost to me,
I lift my lamp beside the golden door!"