> if you take your position to the extreme then there should be NO concept of citizenry.

Yeah. It's just what the first people to go somewhere say when someone else tries to join them. "Take off, we first settlers don't want you here."

We don't recognize first-posters as owning the thread, or (except in the USA) first-solvers owning the formula, so why should we recognize first-squatters owning the land?

> It's all fine and dandy as a theoretical concept but has no bearing (or utility) on the real world.

Not at all. The concept of doing whatever you want is firmly established in the real world. Your adoptive countrymen weren't welcomed here (or at least, not in much of 'here'). They came by force and trick, murdering and stealing.

At least today's undocumented immigrants live in peace.