Trump is waffling on the wall.

[The Grand Nudger]

Only Germany had an actual wall built - because it happened to be shared by the Soviets and the West simultaneously.

Most of it was what you might call a long term improvised defensive line.  The sort that infantry are familiar with building as temporary and then improving upon for so long as the line remains static.  Starts out as footprint shallows. Then foxholes. Then trenches...maybe you drop down some wire, plant a few tank traps...toss out a mine or two...over time it builds up, and you have to have -something- for the folks manning it to do, lol. Just about everyone who builds these walls for any legitimate reason knows that "walls-walls" have long been eclipsed by tech and tactics for both military and criminal applications.  Even the walls at our prison, today...more to keep us from having to look (and keeping them from looking out) than for any practical purpose not better addressed by another form of obstruction or even earthwork.

The value of a wall as-envisioned, is psychological.  That was true in germany, and it was true here, in the states, in this election. Obviously, you don;t even have to build it. For whatever reason, just thinking about it works on that level. Anyone can tell you on which side of a -hypothetical- wall they live. The wall, as such, may only be, at some points, a redline on a map....that corresponds to a seemingly empty field...but everyone knows where it is......they know the kill line, even if it's unmarked.