It is nuanced in that it will cost a ton of money, fly in the face of the whole Christian "love thy neighbour" and "brothers keeper" bits and IT WON'T WORK!
Look at the number of tunnels that Israel deals with and their border is like 1/10th the length of ours. The drug cartels already have lots of experience in tunnel building.
Or there will be the European solution, where they all just s shift to boats -- and I don't mean poking around the corners in Texas and Southern California. I mean 6,000+ miles of Atlantic and Pacific shoreline, not counting Alaska, Hawaii, Puerto Ricoo or the Virgin Islands.
Most likely both, plus routing immigrants thru the 5,500+ miles of Canadian border.
"Build the wall" is a blatant appeal to the "I'm angry, just do something" crowd who is so riled up they've lost the ability to think rationally. It is a pure feel good emotional play, and it will fail. AND cost a ton of money.
If this idiot move happens, I need to figure out what companies are going to get the maintenance and enforcement contacts because it will rival the defense industry for government pork spending!