You assert that this does not apply at the border, but you miss the fact that nowhere in the constitution are these rights set up as exceptions "near borders with other states". All of the amendments that make up the bill of rights are absolute statements, thruout the country.
I think that the legal concept is that "airside" at the airport and the no-man's-land are not proper US soil but some kind of quasi-international place (which is also why foreign citizens are allowed to wander there without visas if they have connecting flights and why you can buy duty-free merchandise there in countries where that's relevant). There's probably a name for this.
So if you walk up to the desk, you're standing on non-US soil and the desk guy is standing on US soil and trying to decide whether to let you across to the other side.
You'll note that the Constitution doesn't actually state where the borders of US soil are.
