Then the answer is “OK, then you start helping the cartels. We’ll be looking to see if there is any difference”.
The link below is a fairly detailed account of just how bad the drug cartel situation is in Mexico. So many have been killed, including government officials. Efforts to take out cartel leaders have resulted in splintering and spreading of smaller more vicious gangs. This is not a simple problem. Trump was right to emphasize treatment for our drug addicts to reduce the US market.
https://www.cfr.org/backgrounder/mexicos-drug-war