Today’s commercial strains of recreational pot are dramatically more potent than that schwag you smoked with your buddies back in 1979. Even since the mid-’90s, the THC content of middle-of-the-road weed has quintupled or more, and commercial markets today are mostly driven by heavy users who crave that punch. How can we predict the long-term consequences when kids are smoking stuff that wasn’t available until a few years ago?

For all its problems, alcohol at least represents a known commodity. And we’ve developed a range of strategies for discouraging alcohol abuse. Traffic cops have breathalyzers in their cars. Standardized labeling requirements keep consumers informed as to what they’re putting into their bodies. Everyone knows that there will be consequences for showing up to work intoxicated, or for overindulging on social occasions. These measures are only partially effective, but they do help. A majority of American adults drink alcohol, but only a minority drink to excess.

In principle we could develop similar checks for cannabis, but it will take a lot more research and development, not to mention years’ worth of cultural adaptation. What will happen in the meantime?