With a virtual “wall” peeps in remote areas would have to be interdicted in Mexico well before they got to the border.
A few mine fields would work!!!
Well, the theory was that you put physical walls/fences where the invaders would have easy access to towns or cities so they couldn’t just disappear into the crowd, so to speak. Then in the middle of nowhere, where there are vast stretches of uninhabitable dessert, you detect them and then pick them up using your fixed and mobile sensor towers and ground sensors. The downside is that yes, that means they are in the US when you apprehend them. At the time, that wasn’t something the government considered important to prevent. I think it was before the scam of asking for asylum from muggers was taken seriously at all, so you catch ‘em you can deport ‘em. I now know Bush would have never done that. In fact, even catching them was too much for Bush so I believe he had Chertoff make sure he picked the most useless solution possible - phones.