alt Hacker NewsThat's just a way to rationalize policies that are obviously anti-liberty. Is the Texas/Mexico border my property? Really? All of it? And isn't abuse of private property anti-liberty anyway? You literally just said it is.
Countries do prevent other countries from using their airspace, by the way.
Preventing people from encroaching on your nation is fundamentally no different than preventing people from trespassing on your property. It's not anti-liberty, since we don't have an inherent right to any land on earth. That right to occupy a piece of land, to the extent that it exists, emerges through homesteading and the principle of First Possession.
As for U.S. territory, yes, you can make a case that it's the collective property of American citizens who then decide how the property will be governed through their elected representatives. How is that anti-liberty?