> But to me it makes no sense to allow anyone to profit from a substance that causes this much harm.
It's possible to use heroin daily for the remainder of your life and have a better health outcome than a cigarette smoker.
The drug war makes heroin use more dangerous. Now you have dirty needles, cut drugs, highly inconsistent doses, lack of free treatment/therapy, fear of police and the legal system that leads to reluctance to seek medical attention, etc. And of course black market violence still exists here and abroad.
"Like most opioids, unadulterated heroin does not cause many long-term complications other than dependence and constipation."
Switzerland had success with the heroin problem. They've made it legal and free, but to get it free, you need to visit a hospital for your daily injection, where they also can give you psychological help.
The program seems to have been a success, destroying the market for illegal heroin, and also reducing demand because it gives the drug a perception of being for losers.
How did they manage it in the 30s (or whenever depending on your nationality)? Are you absolutely certain that criminalization wasn't an overreaction to a problem that after all wasn't all that big?
If you've got a free hour-or-so sometime this BBC documentary is pretty engaging and describes the opiate timeline regarding use and legal status:
https://www.youtube.com/watch?v=I3M1QPoeNMU
It makes sense to decriminalize users/addicts because they are the victims whom drug legislation is supposed to protect in the first place.
But to me it makes no sense to allow anyone to profit from a substance that causes this much harm.