Again the Black market is cheaper than legal production. All you do is shift the market to another nation and that is if the cartels leave Mexico for little reasons. More so depending on how far legalization goes the laws could ends up removing vital mid and low level criminals from flipping on their suppliers as there is no crime.
There is a gray area in which various legalization laws create in drug deals. Canada is learning the hard way right now. First off is local laws and government which can shutdown any legal production via regulation and bylaws. The next level is provincial using the same methods just one level up. Legal product of weed cost twice the price to customers than the black market. Wage laws must be followed. Building codes. Health codes. Etc. Legalization has shifted some violations to be about licensing instead of a major crime. A low level deal is no longer a drug related crime with narcotics but merely an unlicensed business exchange. Weed isn't even covered by pharmaceutical laws. It is just an age limited consumer product. Without the penalties of narcotics violations police can only go after major individuals or group typical breaking border laws. As Mexico has far more issues with law enforcement in general the cartel's risk does not change locally. Internationally using mules is still the same. The only change is a nation sends less of it's citizens to jail.
The only real world example we have to compare it with is the end of Prohibition, at which time a lot of the gang wars over liquor subsided. It obviously didn't end crime or organized crime, but at least it resolved the immediate problem at hand. It doesn't mean that there hasn't been problems, as alcohol and alcoholism are serious problems in society. Legalization is not a panacea by any means, but at least it might bring some semblance of order out of chaos.
I also realize that the cartels won't necessarily go away, although they might be weakened in power. My sense is that a lot of the cartel violence isn't just about drug dealing either. Considering how brazen some of these attacks have been (such as mass murders of cops, shooting up hospitals, slaughtering whole villages), it's almost like rival factions of warlords which rival the official government. US crime families, as bad as they might have been, never really got that extreme or radical. Not like these cartels, who seem reckless and self-destructive.
They also have operations in the US. I've seen reports of safe houses linked to the cartels being discovered around here. They're connected to powerful street gangs in the US, as well as prison gangs. That's part of the problem, since prison is hardly any real deterrent. I don't think we can stop gangs and cartels entirely, but the only reason they're a major problem today is because of the economic power they wield from the lucrative profits in the drug trade. Financially, they're on par with any major Wall Street corporation.
I'm not saying we can eliminate the black market entirely, but it can be weakened - and that may be an adequate, albeit imperfect, solution to the current dilemma.
Tragic that the children died, though. However, that cult has its own nasty history of murder and abuse.
