Americans have long since broken free of their Puritan past, but the Puritan impulse is not quite dead. Among the places it shows signs of life is the 1992 federal law that prohibits states from — you are not going to believe this — allowing betting on sports.

If a Martian arrived today, of course, she would deduce that in this country, betting on sports is not forbidden but mandatory. March Madness costs businesses an estimated $4 billion a year in lost productivity, and it’s not because employees waste time singing their fight songs.

Gambling has been around longer than the country itself. The American Revolution was financed in part by a lottery, for heaven’s sake.

But the urge to suppress this vice is just as old. That’s how we got the federal law — which is under review by the Supreme Court in a case that arose after New Jersey defied the ban by passing legislation to permit wagering on athletic contests. The federal law may survive the justices’ scrutiny — though veteran court watchers are betting against it — but it isn’t likely to survive changing mores for much longer.