However, I think there needs to be an incentive to not use, so some sort of mandatory treatment program might be a good idea, or perhaps it depends on the drug in question.
Do you think those recreational drugs that have been shown to have minimal serious side effects should be legal, at least? (marijuana, LSD, MDMA, etc?) Do those drugs even need a particular incentive to disuse, since they aren't really any more dangerous than any other hobby, and the existing disincentives to continue a hobby beyond reasonable limits would still apply?
I'm not sure I'd consider a powerful hallucinogen to be no less dangerous than "any other hobby". Granted, that depends on the hobby you're talking about; people are allowed to climb mountains, after all.
But honestly... I don't know, because I don't know how safe those drugs
are in the long or short term. I would probably have a more solid opinion, but most of the information out there originates either from the Official Government Lie Machine™ or people who are way, way,
way into drugs and have an obvious legalization agenda.
I want to say LSD is surprisingly harmless (aside from the obvious messed-up state while you're on it, but only then to a certain degree), but then again, it can also apparently cause psychosis in some people, and there's hallucinogen persisting perception disorder to think about as well. From what I'm reading, the safety of MDMA is pretty up in the air regarding potential long-term side effects.
Marijuana is a complete joke, though. There's no reason why marijuana shouldn't be
at least as legal as tobacco. That being said, I wouldn't want to see it turned into some kind of mass corporate commodity, but that can probably be controlled well enough via taxation on sales and restriction on growing operations. Then again, I'd probably say the same about tobacco.