Being in a border state, I can tell you a third problem: private property. The wall was supposed to go through several persons' private property, and they were none too happy about it. I don't recall now if some of them were suing, but likely at least a few were. I believe this was in areas which the wall could not be built along the border, and so had to be built a mile or two on this side.

Which, if I recall correctly, elicited complaints from pro-wall people about "why are we giving Mexico some of our territory".

It was a mess.

But I think I'll help the anti-immigrant folks out here...why can we not enforce labor laws regarding the undocumented? When 1poorlady first came to this country, our HR department carefully tracked her documents, and asked for updated documents when expiration dates were nearing. It would require Congress to do ONE thing: heavily fine a person or company that knowingly employed an undocumented worker.