from a real human welfare perspective, we ought to put a lot of weight on making sure that people with chronic pain get the best treatment possible. Minimizing addiction is a fine public policy goal, but the priority should be on making sure that people with legitimate needs can get medicine.
In order to sound "reasonable" to moral monsters, Yglesias gives away the game there: The fight against "addiction" is a rich enough fantasy to feed any amount of horribly restrictive laws and actions against people using medication. (See our extensive coverage of the Richard Paey prosecution lunacy, as a paraplegic got a 25-year prison sentence in Florida, for which he was later pardoned, essentially for using too much prescribed medication–and doctors in prison realize he needs even more of it than he was arrested for taking.)
Reason's Jacob Sullum wrote the journalistic masterpiece on the topic of the insane legal war on pain meds back in our January 1997 issue.