That's mainly because it cuts into the US government profit margins. They and their favored contractors have been selling arms for profit and love drug running when it suits their aims as they showed with eg support for the Contras.
It is important drugs stay illegal so powerful connected interests can maintain high profit and control. Without that, simple cocaine/meth/marijuana is just an agricultural or chemical commodity with essentially the margin of generic OTC drugs.
The US government does not have profit margins. It hasn’t run a balanced budget in decades. What are you even trying to say?
Yeah I meant more like some shady fentanyl that overdoses people en masse, not some rather harmless and sometimes even beneficial weed.
The worst part are weapons, there is no way to spin it as something benign. Victor Bout for example got 25 years and there was no drug smuggling nor contract murders.