Look how the Mexican cartels have taken over the the meth market which used to be small and localized.
Do you know why the Mexicans were so easily able to take over the meth market? It's because of they already had smuggling routes and huge marijuana distribution network they could run the meth through. Mexico has always been a marijuana producing country and even before the Sixties they were growing marijuana and it was being smuggled into this country. We used to get marijuana from all over though, from Jamaica, Panama and other countries in Central and South America, from Asia, etc. We used to get a lot of Middle Eastern and African hash too. The Mexicans took almost all that business though. They were uniquely situated on our Southern border such that they had easy access to this country and all drugs coming from below Mexico had to come through Mexico if they went by land. At first much of not most of the pot coming from Mexico was grown their and picked up and brought in by people in this country. Slowly but surely they took over smuggling and distribution up to the point now that they are often selling to the person selling to retailers or are only a level or two above that. They also produced and smuggled a small amount of heroin in and were making inroads in cocaine smuggling and distribution and eventually took over most all the cocaine smuggling and distribution business and completely edged the Colombians out of the US pot business. Now the Colombians sell their pot in their region mostly and they sell most all their cocaine bound for the U.S. to the Mexicans and let them worry about smuggling and distributing it.
The Mexicans have been involved with meth for a long time though and took over the meth market long before you might think. Even before the controls on pseudoephedrine were put in place here the Mexicans were supplying almost all the meth in this country. Little kitchen meth labs usually produced only a few grams at a time most of what they produced was consumed by the cooks and all their little helpers. They'd sell a little a little but it was a drop in the bucket compared to the big amounts being brought in by the Mexicans. For decades most of the meth available on the market has come from big labs. These “superlabs” produce batches of 10 pounds or more and they keep these places running day and night turning out batch after batch. Mexicans have been producing tons and tons of this stuff for a long time now, and just running through their existing distribution networks.
Marijuana is the most popular illegal drug. Far more people use it than any other illegal drug. Cocaine is the second most used illegal drug in this country but total demand for all the cocaine, meth and heroin consumed here is in the hundreds of tons compared to many thousands of tons of marijuana. It is their most profitable drug, and it is the one that they are able to reach the most people with. When we take it from them, the black market for illegal drugs will shrink to something much smaller with far fewer participants, users and sellers. When we take marijuana from Mexican organized crime, they are no longer going to have access to most of these former participants in the black market for illegal drugs. Licensed pot stores aren't going to sell their cocaine and meth for them. Taking marijuana is going to hurt them not only by depriving them of most of their income, but it's also going to make it harder for them to move their other far more dangerous drugs.
These organizations have already branched out into other criminal activities and will no doubt try to do more of that if we take marijuana from them. But their not going to be able to replace these billions and billions of dollars in annual income they'll lose. There will not be enough money to support such big and powerful organizations and they will shrink and become less powerful and less of a threat. And fewer people are going to be attracted to that lifestyle to begin with because there won't be nearly as much money to go around. In the end there should be less crime and less corruption for us to deal with.