I’m saying that serious attempts at immigration control should focus on the employer. For the US that means strengthening eVerify, which is currently strictly optional if you are not a government contractor. E-Verify - Wikipedia There are all manner of ways to fairly clamp down on employers who hire illegal immigrants.
In northern Europe, illegal immigrants are forced to work in the underground economy, if I’m reading the subtext of this paper properly. In other words they can’t easily secure ordinary jobs like they can in the US restaurant, farming or construction industries.
Because unenforced laws are very similar to no law at all.
Don’t get me wrong. Frankly I think this whole debate stinks of nativism. I’m almost indifferent between halving or doubling aggregate immigration quotas. I’m just saying that the proper focal point for immigration control is at the employer level. It’s not like somebody who overstays their tourist visa does any harm if they are just spending money here and are not receiving governmental funding. And discussion of border walls is silly.