Saletan wonders:

Drugs can be, and are being, re-engineered every day. Nicotine and caffeine appear in new forms. Cannabis is an herb, then a powder, then a capsule, and now a spray, with significant chemical adjustments along the way. (....The Marijuana Policy Project argues that the spray formulation has already been eclipsed by a better way to filter and deliver the drug's therapeutic benefits: vapor.) How do you fight an enemy that keeps changing? How do you recognize when it's no longer your enemy?
Every feat of re-engineering challenges our moral and legal assumptions. In the case of Sativex, two positions are under attack: the left's lazy tolerance of recreational marijuana in the guise of legalizing medical marijuana and the right's opposition to medical marijuana on the grounds that it's just a pretext. By refining, isolating, and standardizing pot's medicinal effects, pharmaceutical companies are showing us how to separate the two uses. Are you for symptom relief or getting stoned? That used to be a fuzzy question. Now it's concrete: Do you want the reefer or the spray?

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