I'm pretty sure if a wall in your house goes down it'd be a day of sadness for you. They say good fences make good neighbors, but it also depends on the neighborhoods (btw, check out rich houses - do they have walls and fences? do they have gates? do they have another gate around the community?) - and if you have https://en.wikipedia.org/wiki/Tijuana_Cartel as your neighbors, you may think a wall going up between you and them is not such a bad thing.

> The thing to keep in mind here is that such walls built to keep others out can be used just as easily to keep the locals in (on either side).

Somehow I'm not too worried about not being able to escape from the US to Mexico and the US trying to keep me in. I think you need to rob a bank or something to make that happen?