As cold medicine regulations on pseudoephedrine got rid of all the "shake and bake" labs in Tennessee, around 16,000 of them, the loss of marijuana traffic, evolved into super labs in Mexico, that produced purer and cheaper meth. Much more deadly than ever before.
Just as in Tennessee, we see cartels in Dayton, Ohio, becoming the largest entry point for heroin the midwest. In Kansas, Mexican traffickers were just busted for importing heroin. It's become a constant theme. The cartel that used to sell just south of the border, has moved north of border cities. No longer just large urban, but small rural communities. Their tentacles have grown and distribution centers are all over the United States.