Lol you're deliberately missing the point. Also, > Closing every single border crossing at the same time in a period of instability isn't going to be trivial.

Lol you're deliberately missing the point. Also, > Closing every single border crossing at the same time in a period of instability isn't going to be trivial. At least here in the US, literally every single border crossing is already guarded by armed men. They can already close them on a whim whenever they want.