And there's good reason to be skeptical that legalization would yield the sort of huge increases in use/abuse that Kleiman predicts because, well, drugs of all kinds are readily available to anyone who wants to experiment with them. Cocaine and heroin are just as available now as they were in 1980 and these drugs have become a lot cheaper since then, too.
But even if Kleiman is correct that drug abuse will increase as a result of legalization there also would be significant positive outcomes from legalization that, I believe, would more than offset the negatives. Spending on prisons and jails--which is unacceptably high--would decrease. Monies would be available for treatment which has a much greater effect on reducing demand for drugs than arrest and prosecution. Law enforcement would be freed up to deal with violent, truly harmful crimes such as rape and armed robbery. Much of the profits would be drained from the cartels currently destabilizing our neighbors across the border.
No drug policy will yield entirely positive outcomes. But we currently have a drug policy that has brought consistently, overwhelmingly awful results--the highest incarceration rate in the world, steady availability of illicit drugs, the under-funding of treatment, dollar eradiction plans in Colombia that simply fail and waste billions of dollars in the process--and legalization, while not perfect, would remedy many of the negatives.
