Hi Drac. We know what wall I'd suggest... And Mexico would pay for it.
Interestingly enough, while they come through Mexico, the majority of illegals coming across the border aren't Mexican. They are coming in from central and South America, as well as Asia and the Middle East. I can't find it now, but thete was a news article a few years back where Mexico caught a truckload of people trying to sneak into the US. I want to say there were 20, but there could have been more. Over half were from South of Mexico, but the rest were from China, India, and the Middle East. Meanwhile, for the last decade, the number of undocumentef Mexicans leaving the US is in the millions.
Go figure.