I think there's a good chance that you'd be shot at by US law enforcement if you tried to make an end-run through a border checkpoint, regardless of which direction you're going. In fact, they might even be more aggressive in the US -> Mexico direction (because follow-and-detain is less of an option and the presumption that anyone heading that direction illegally is either smuggling or evading arrest).

> But East German border guards were shooting East Germans who were welcomed by West German guards. Pretending that this is a typical state of border affairs is gross revisionism.

Of course. I think the point still stands.