The fact that prohibited drugs are nevertheless so widespread, that it is trivial to get access to them if you want to, is prima facie evidence that prohibition doesn't work. Opiates (and other drugs) are already for sale on every corner. I don't see any evidence that'd demonstrate that their legality or illegality matters one bit. From the buyer's perspective, it doesn't matter because the likelihood of enforcement affecting you is extremely low (and consequently, risk/benefit ratio is so low, the risk just gets ignored). From the seller's perspective, the extra risk of an illegal activity just gets factored into the price.
"The fact that prohibited drugs are nevertheless so widespread, that it is trivial to get access to them if you want to, is prima facie evidence that prohibition doesn't work"
This is false. It is not trivial to get hard drugs. Most people have no idea how, and if they go that route it's risky.
If drugs were allowed to be in the corners store, you'd see a 100x increase in their use.
Drug prohibition keeps drugs in relatively small terms. Without it, it'd be as common as beer or wine.
