Militarizing the border and a physical barrier will be the only solution.
Tariffs incentivize cooperation.
“INSANE: Cartel Gunmen Reportedly Brandish Rifles, Intimidate Border Wall Construction Crew”
“Wall construction workers received a reported intimidation attempt from cartel gunmen last night.”
https://bigleaguepolitics.com/insane-cartel-gunmen-reportedly-brandish-rifles-intimidate-border-wall-construction-crew/