We don’t need a multi-billion dollar wall. We need to make life so inhospitable for illegal invaders that they no longer find it worth their troubles to come here in the first place.
I don't think, with the vast sums of money to be made, that the drug cartels aren't going to stop trying to get their loads here. Besides, the wall would be a symbol of our sovereignty for the world to see. Also we need to make hiring them "inhospitable."