Each physical store can have different prices on the same goods, to exploit the average differences between the populations in each area. Already happens between countries/continents, now it can happen on a neighborhood scale.

The US controls the ocean. They don’t need to fight a ground war. Trump’s play is very clear: “Give it to us, because you can’t stop us taking it.” So it’s weird he’d sell weapons to Denmark. Makes it look like he’s bluffing. I wonder if he’ll now very publicly stop the sale. That’d be the right move, even if he is bluffing.

How will you get them there? The US controls the ocean. I suspect they also control low earth orbit and so will be constantly watching.