MANY CITIES now prohibit smoking in outdoor parks, beaches, or public squares, so there is nothing surprising or original about a proposal to impose a similar ban in Boston. City Councilors Felix Arroyo and Salvatore LaMattina have introduced a measure that would make it illegal to light up a Marlboro in many open-air venues, and they justify it with the usual nanny-knows-best pieties about health and children.

“We want these public places to be smoke-free so that everyone can enjoy . . . our public spaces without injury to their health,’’ Arroyo declares. “We don’t want to expose our young children at the tot lot. We don’t want to expose families at the beach to smoke.’’

LaMattina says he resolved to seek a ban after watching a woman who was sitting on a park bench get up and move when a smoker appeared. He was indignant. “If people want to smoke, it’s their business. But when you’re in the park or the public space, I think people should smoke away from the public.’’

It’s an asinine proposal. Anyone who is sensitive to secondhand smoke can easily avoid it outdoors. Moving to another park bench or stretch of beach to get away from a cigarette may be annoying, but it isn’t the purpose of law — or the City Council’s job — to protect us from every conceivable annoyance. If the councilors were proposing to ban noisy children or trashy dress from public parks, who would take them seriously? But come up with another way to crack down on smoking, and virtually no restriction is beyond the pale. Why?

I am not now and never have been a smoker, I don’t like being in smoky rooms, and I impress on my kids (one of whom has asthma) the health risks of using tobacco. But contemporary opposition to smoking goes far beyond prudence about health risks. For some reason it has turned into a moral crusade. American society has been gripped by the conviction that smoking is not just unhealthy but immoral; not just a poor health choice but a shameful failing. Cigarette smokers have been transformed into modern outcasts, shunned and ostracized lest they corrupt the rest of us.

What explains this? No other personal habit is demonized as incessantly or banned as avidly as smoking. Americans who like to drink aren’t stigmatized in this way; why are those who like to smoke? Many of the same people who support every proposal to restrict tobacco would roll their eyes at anyone who called for reinstating the prohibition of alcohol. Why the difference? Alcohol has wrecked more marriages, caused more accidents, and fueled more crime than smoking ever has. Cigarettes may make you ill, but they won’t ruin your character or debauch your lifestyle. Yet elite opinion is ever-ready with new restrictions on the right of adults to smoke; the right of adults to drink it leaves in peace.

Why, to take another example, doesn’t the coarsening of American culture whet the nannies’ appetite to regulate and restrict? From TV to popular music to advertising, after all, leering raunchiness and potty-mouthed crudity have become almost ubiquitous. Back in the era when far more people smoked, it would have been unthinkable to drop F-bombs in public as a matter of routine. Yet while smoking in public has become low-class and despised, nonchalant vulgarity is relentless and unashamed.

And even celebrated. One of the nominees for Record of the Year at the Grammy awards tonight is a profanity-laced song titled “F*** You.’’ The assembled glitterati will doubtless applaud energetically when the song is announced — but not one will light a cigarette anywhere inside the Staples Center.

It’s true, as the anti-tobacco crusaders endlessly stress, that smoking pollutes the lungs and heart. But filthy language is pollution too: It pollutes mind and mouth and soul. I don’t want my kids to smoke because I care about their health. I don’t want them to curse — or be exposed to the constant cursing of others — because I care about their character. But our modern warriors don’t think about character. They’re too busy making sure that we all live forever.

So Arroyo and LaMattina’s ban will no doubt be adopted. The anti-tobacco crusade will claim another victory. It doesn’t flatter the city councilors, or the voters who elect them, that this is their idea of a worthy cause.

Jeff Jacoby can be reached at jacoby@globe.com.

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