Jim Leitzel of the University of Chicago has done what most proponents of drug legalization refuse to do: Â admit the likely increase in drug abuse as a result of legalization, and think in concrete and practical terms about policies to limit that increase, such as requiring each user to pass a basic-knowledge test for each drug and set a personal quantity limit for each (day? week? month?), and banning sales to, and use by, those convicted of crimes under the influence. I’m less sanguine than Leitzel about the practicalities; since the 10% heaviest users of any drug consume at least 50% of the quantity, and since heavy users are more likely to be problem users, even a moderately tight licensing system could create the customer base for a huge illicit market. But he’s at least asking the right questions, and trying seriously to answer them. Note that favoring the sort of regime he proposes for cannabis still makes you a wild-eyed permissive liberal, while suggesting it for the far more dangerous drug ethanol makes you a fun-killing nanny-state liberal. “Conservatives” seem to be perfectly satisfied both with cannabis prohibition and with insane laxity about alcohol.