When most of us peer at the man in the moon, we think of poetry or space pioneers. Not Wilbur Ross, the US commerce secretary. “The man in the moon is going to become a gas station attendant,” he recently told the Milken Institute’s global conference.

“To get big payloads [into space] it makes sense to first go to the moon and then refuel,” he added, by way of explanation. “When you do a launch you need hydrogen and oxygen [and since] the dark spots on the moon are ice?.?.?.?you convert the ice into fuel and then off you go to Mars.”

Just a flash of indulgent fantasy? After all, no one knows whether the water on the moon is accessible. Some investors might think so. And in a week when markets are reeling from the Department of Commerce’s threatened trade wars, it is tempting to ignore this chatter about outer space.