[quote=cr]…Pot is a drug, like heroin, coke, etc. You legalize one, where does it stop? ….how do you justify legalizing this, but not that, and minimize the risk of raising a generation of tweakers?…[/quote]

I think you found your answer about drawing lines. Each drug would be studied for its economic effects, primarily on the non-users. Those that cause high costs would continue to be limited. But the degree of the limits and the particular form of the limits would be designed solely to minimize the total costs to the rest of society. Methamphetamines would be hit hard, perhaps with the full criminalization we have today, whilst pot would be taxed like tobacco and sold in the same stores.