That actually a very smart move. By legalizing it all, cartels won't have any sources of income because superprofits would disappear.
Ummm I think the narcos are going to take control of the market anyway, either legal or illegally... In fact, by legalizing drugs, they are giving the cartels the option to "come clear" and to declare and have their money clean almost instantly.
I doubt they will lose any profit, but, how knows? Maybe legalization is the way to the peace in Mexico. And yes, we absolutely need some peace.
Don't the cartels make a lot of money sending those drugs to the USA (thinking mostly cocaine). I thought Mexico was the pipeline to coke entering the States? What percentage of cartel revenue is distribution in Mexico vs exporting? If the violence in Mexico is doped up junkies shooting each other or gang turf wars over who can sell where, legalization might work. If the violence is cartel driven at a higher level, like we saw during the Medellin/Cali/Escobar days because their business was almost purely export, then legalization I don't think will help.
I don't know enough about the specific violence in Mexico and I am curiously following the thread!