I watched a NatGeo show about the illicit fentenyl trade from Mexico to the US. The Mexican cartels relied on smuggling the precursor chemicals from China. The goal of the cartels is to domestically source those precursors.
Disturbing how the drugs get more potent but that does make sense because addicts need a bigger hit. Marijuana has gotten much more potential too. During my lifetime, went from heroin and cocaine to crack then meth and oxy to now fentanyl.
next up is carfentanyl. exponentially more powerful than fentanyl.
I watch that show every week. Scary.