Mexico cant do anything.
I have a student who I've discussed here whose Father (currently deceased, drank himself to death) was in the Mexican Military. Cartels assassinated every member of his unit, and some of their families. He fought alongside US troops, know what he got for his trouble? Deported. Thankfully his kids got asylum, one of the cases I wrote a letter for, his oldest Son.
Mexico wont legalize drugs and allow for a legal market. It would change the Country overnight with regards to violence. From there it will be about containing the market the same way we do. It wont be pretty, but other Countries did this and it worked. The only argument I've heard against it is "cartels will still behave like cartels"...yeah ok, but we deal with medicine and oil cartels all the time. There is no real structural difference between a giant corporation and a cartel, mainly just legal distinction.
Mexico adopted out drug laws under threat BY us, the work of Henry Anslinger, a guy who thought weed turned people into psychotic killers and the main guy most directly responsible for the death of Billie Holiday.