As recreational drugs go, marijuana is relatively benign. Unlike alcohol, it doesn’t stimulate violence or destroy livers. Unlike tobacco, it doesn’t cause lung cancer and heart disease. The worst you can say is that it produces intense, unreasoning panic. Not in users, but in critics.

Those critics have less influence all the time. Some 18 states permit medical use of marijuana, and in November, Colorado and Washington voted to allow recreational use. Nationally, support for legalization is steadily rising. A decade ago, one of every three Americans favored the idea. Today, nearly half do — and among those under 50, a large majority does.