Seems this ongoing conversation about legalizing drugs rarely touches on drugs that are legal but requiring a prescription. For many of the same arguments in favor of legalizing "street" drugs, do you think narcotic pain killers should be available "over the counter"? Personally, I don't think so, but then, I oppose legalizing drugs.
Tough question given the factors in play.
I'm definitely in favor of decriminalization of everything.
I'm definitely in favor of legalization with restrictions - like alcohol - for anything
less addictive and harmful than alcohol, which is actually most drugs. Then you have a few that are even more addictive and cause even more health/social/economic damage to the addict, like meth, heroin, crack, powder cocaine. (I don't say more harm overall because alcohol and tobacco have the lead in total harm, but that's in part due to legalization and full availability)
I know I don't want CVS selling baggies of heroin next to the tylenol; I think countries like Switzerland have the most sensible approach when it comes to a drug like that. Namely, set up clinics where you go, admit you are an addict, and get administered a controlled dose of pure heroin. There's no evidence that people are going through all the hassle just to try out heroin, rather, the effect has been a reduction in overdoses. At a certain point, reducing harm is all a policy can do.
Of course, the problem with decriminalizing personal possession but keeping it illegal for people to sell heroin on the street means that violent armed gangs can fund themselves via drug sales. (Indeed, organized crime only exists in America because of our experiment with ethanol prohibition). I suspect it would be extremely hard to puzzle out (1) precisely how much use of drugs like heroin would increase if we didn't fight the Drug War at all, ie, full legalization with regulation rather than decriminalization, and (2) whether or not this would be balanced by the reduction in overall harm from severe weakening and/or obliteration of violent drug gangs that would result from their revenue disappearing.....
...they can't all just switch to burglary or join the mafia.
I suppose I still haven't entirely made up my mind about what the best policies for things like heroin (and I include perscription opiates given that they're all in the same general family, with the same general risks - it's just that heroin is the riskiest).
Of course, it can be borderline impossible to have a rational and dispassionate discussion about this on the national stage. Too many people have some religiously derived or elsewhere derived ardent opposition to decriminalization/legalization "because drugs are bad mmmkay..." Too many politicians find it easy to get elected pandering to those people. And of course, addiction is a very real and damaging thing, so tons of people will have a personal experience with addiction, be it themselves, their family, or their friends. It is naturally much harder to take an objective view on something like this if one has had a first hand damaging experience versus not.