On the subject of the money, 250 billions dollars leave america to pay for those substances (who hurt only the users). Why not have a domestic production? It results in a lower price and constant predictable potency&quality for the consummers and taxes for the commmunity while the money stays in the usa and more income of the users can be put to other uses.
A lot of death in this domain are related to the toxicity of the product because of the illegal trade and unabiliy for the users to determine their dosage... it's like alcohol during the prohibition, you never know until you tested it.
And demand reduction is easly done with information and safety education, specially when well financed with tax on the users...
In short the loop is to drive the price lower (included taxes) than illegal pricing and by these financing prevention, information etc to reduce demand with the money of those addicted today. ...
It's always better to start with reality. Blaming ghosts and creating fake monsters is drama but does not solve things. The old movie 'reefer madness' https://www.youtube.com/watch?v=aYHDzrdXHEA was about as helpful as McCarthyism.
There is nothing wrong with something having a natural risk. If you drink a lot you could get alcohol poisoning etc. But there is something wrong with criminalizing the natural risk and replacing it with an artificial one.
There are loads of people dying every day from bizarre polluted forms of opium, made into pills and sold at ridiculous prices. And aside from deaths a huge toll in crime and misery.
If opium were available a lot of people would smoke it, very few would die, a few would eat it, there would not be even close to the mortality that pharma opiates have.
The really amazing thing though is that the pills that people pay so much for are garbage compared to real opium. Real opium is pleasant and harmless, the pills kill a lot of people and numb them instead of helping them.
A few years ago you got mandatory jail for having marijuana within a certain distance of a school. Now in some states there are marijuana stores very close to universities. Opium is next and it will do good things for society. Some links on both sides
https://drugs-forum.com/threads/heroin-vs-opium.7818/
https://www.quora.com/Whats-the-difference-between-opium-and-heroin
http://www.skycitygallery.com/hk/hk.html
http://www.countercurrents.org/us-polya281005.htm
But you are talking about plants. Things that grow in the ground and existed long before any government. The problem is not with the plant and it is a misguided effort to restrict plants. It is nice to try and blame the plant 'oh it is an evil plant etc' but to solve a problem it is better to start with real reality, not specially modified and adapted reality.
If ancient people who had no science, no reading no internet were able to withstand the attack from plants then we do not need today the government to save us from marijuana or opium by forcing an industry of synthetic drugs.