Earlier quoted context omitted.
What you're talking about is basically a surveillance based internal border. It can work that way for people if you have massive levels of internal surveillance (otherwise how do you think the government can catch employers of illegals with any efficiency), but it doesn't do much for goods or people who cross the border without wanting to get a job, like gang members, dealers etc.
> What you're talking about is basically a surveillance based internal border. It can work that way for people if you have massive levels of internal surveillance (otherwise how do you think the government can catch employers of illegals with any efficiency) What you're talking about is called law enforcement and it has existed in this country for a long time. Until you clarify your point (what are "massive levels of…
Are they just coming up here because they feel like it, or are they responding to some kind of demand?
That's incoherent. They're moving because they can earn more money in America. The fact that there are people who 'demand' lower wage workers is irrelevant: there will always be market demand to get more for less. The issues with immigration aren't on the employer's side.