It started with an unsubstantiated rumor. “You can laugh now,” Johnny Carson said on The Tonight Show on December 19, 1973, “but there is an acute shortage of toilet paper.” There wasn’t—but it didn’t matter. The broadcast sent America into a mass panic. Millions of shoppers swarmed into grocery stores and began hoarding toilet paper. Ex nihilo, a shortage was born. The Scott Paper Company urged people to stop panic-buying the product. Nevertheless, for four months, toilet paper—absent from shelves—was bartered for, traded, and even sold on the black market....Some experts regard the toilet-paper shortage of ’73 as a...