"With any luck Trump will... build a wall along the Mexican border to keep the drug cartels... out of the U.S."

This person seems to be under the delusion that drugs are smuggled into the US by Mexicans hiking across the border with backpacks full of contraband. In fact, most of the drug traffic from Mexico comes into the US either hidden in vehicles passing through manned checkpoints, via tunnels dug under the border, or by boat. Exactly how a wall could affect either of those smuggling modes is a mystery to me.

Anyway, as has been said before, "If the US builds a 12-foot wall, it will only prove to be a financial boon to Mexicans making 13-foot ladders."