Herman Cain has been much run-down in the news of late. Murky finances. Sexual harassment allegations. Subpar singing.

But I’d like to say a word in his defense. Not only does Cain have a mustache, but he has also left a true legacy: the greatest anti-smoking ad in history. Yet no one has thanked him!

On Sunday, CBS News’s Bob Schieffer confronted Herman Cain about the smoking in his unconventional campaign ad.

“It sends a signal that it is cool to smoke,” Schieffer said.

Did he watch the ad?

In the ad, Herman Cain campaign chief Mark Block endorses Cain, takes a drag on his cigarette and exhales pointedly into the camera. It is the sort of exhale that is intended to look nonchalant and cool — performed by Mark Block, Herman Cain’s campaign manager.

If you, at any point in the ad, as a sad sepia-toned man with a mustache rambled and puffed dramatically into the camera, thought that it was cool to smoke — surely you were smoking something different before the ad began.

I didn’t even want to vote for Herman Cain after watching the ad, and that was the ad’s stated purpose!

That ad did not glamorize smoking. That ad revealed the real lives of smokers in all their horror. Barack Obama used to smoke, and he is now president of the United States. Mark Block currently smokes, and he is the campaign manager of the Herman Cain campaign. This embattled, bizarre organization can’t even hire an actor to star in its ad, let alone tell Herman Cain not to do that creepy, creepy smile at the end of the video that looks as though he is stroking an exotic cat with a pair of baby shoes just below the level of the screen.

Herman Cain apologized to Schieffer. He should never have apologized. He should have demanded a medal.

There will never be a more effective anti-smoking PSA.

“Kids, go ahead and smoke,” the ad says. “You, too, can become Mark Block, Herman Cain’s campaign manager, a man with a mustache who was once banned from Wisconsin politics for three years for failing to comply with election laws. YEAHHHH!”

I have been forwarding this ad to all my smoker friends. “I think there’s something you should see,” I mutter.

Later they call me, sounding chastened. “You’ve turned my life around,” they say. “I just flushed all my Marlboros and donated $8 to the Romney campaign.”

“I’m so relieved by the first part of that,” I tell them.

Listen, FDA. Your warning labels needed work anyway. Coughing babies? Please. Those are just talented coughing baby actors. Corpses? They look too much like Fred Willard to convince. Black lung? The only time I see pictures of lungs is on cigarette warning labels, so I assume that’s just how normal lungs look.

Just cut out a picture of Mark Block and glue it to your cigarette cartons, and I guarantee that sales will plummet. Nothing will ever induce me to smoke again. “Did you see the Cain ad?” I will mutter. “No thanks.”

Herman Cain has not made an ad for himself so much as he has made an anti-smoking PSA for all time. The man deserves some credit.