Steven Shainberg, director of the speculative Diane Arbus bio,


, has a story:

"I was developing a project for a studio, and the character was this totally messed-up guy. He was in his mid- to late 20s; he frequented whores; he took an enormous amount of Ecstasy, and in many, many scenes he would smoke.

"Well, the studio was obsessed with him not smoking. And I used to say, 'The guy's doing all these other crazy things, you're worried about him smoking?' "

Very worried.

Last week, the Motion Picture Association of America announced that cigarettes will now be a factor in movie ratings. In a statement, the body responsible for those parental advisories - the PGs, PG-13s, Rs and NC-17s accorded for scenes of sex and violence, for profanity, drinking and drugs - noted that "depictions that glamorize smoking or movies that feature pervasive smoking outside of a historic or other mitigating context may receive a higher rating."

Fine, smoking kills. Studies from the Centers for Disease Control and Prevention have linked movies to teen smoking, and health organizations, youth advocacy groups and outfits like Morality in Media have long lobbied Hollywood to kick those butts off screen. (Morality in Media wants any film featuring a lit cigarette to get an automatic R.)

"Think about it," wrote consumer advocate and activist Ralph Nader in a "Tobacco and Hollywood" editorial. "The movies are glamorous, and they portray smoking as glamorous, whether or not it is a good guy or bad guy lighting a cigarette."

With that kind of logic, it was only a matter of time before Hollywood officially ceded.

"Smoking is increasingly an unacceptable behavior in our society," Dan Glickman, president of the MPAA, said in his statement last week. "No parent wants their child to take up the habit. The appropriate response of the rating system is to give more information to parents on this issue."

OK. But where is all this going? What's next - an R rating for a scene of grade-schoolers scarfing trans-fat doughnuts? What about a movie that offends vegans - stars chomping on meat, wearing mink, stopping the Mr. Softee truck for a vanilla cone? And who's going to protect the moviegoing public from all the other potentially destructive, addictive activities "glamorized" in the movies?

Playing the tables in Vegas? Lucky You, outta here!

Fashions in film? The Devil Wears Prada, bad for couture-aholics!

Or how about an NC-17 for Spider-Man 3? Swinging from skyscrapers, dangling 60-stories above moving traffic on the slender strands of an arachnoid web - that sort of behavior shouldn't be encouraged.

If the MPAA were to go back and retro-rate vintage Hollywood fare, Turner Movie Classics would be out of business. Can you picture Bette Davis or Marlene Dietrich without a lipstick-smeared cig?

In the tar-black 2005 satire Thank You for Smoking, Aaron Eckhart, playing a slick Big Tobacco lobbyist, tries to get the moguls to put cigarettes back into their movies. Exhibit A: To Have and Have Not, the film that introduced the sultry 19-year-old Lauren Bacall to the world, waving a cig at Humphrey Bogart and saying "Anybody got a match?"

"The greatest on-screen romance in film history," Eckhart exclaims. "How did it start? With a cigarette."

The problem with the latest pronouncement from the MPAA isn't that it borders on censorship - the studios are already busy employing their own goofy brand of self-censoring (to wit, Shainberg's anecdote), and the MPAA has been issuing its inconsistent edicts on everything from female nudity to obscenity, from gore to gayness, for decades now.

It's that it borders on hypocrisy.

Despite the deadly toll of firearms in the United States - fatalities averaging 30,000 a year, and injuries, around 100,000 - Hollywood has no problem sticking a pistol in Brad Pitt's fist or showing A-list celebs wielding automatic weaponry in bus shelters and on billboards promoting the summer blockbusters.

And the MPAA has pasted a lowly PG or PG-13 on slews of films that depict carnage 100 times more lethal than what occurred last month at Virginia Tech. In the Nicolas Cage time-travel thriller Next (in which Cage smokes, by the way), Euro-terrorists get hold of a nuclear device and plot to explode downtown L.A., killing millions. The pic's final 30 minutes offer blazing shoot-outs, rife with ricocheting ammo, the flying dead and falling wounded. Next's rating? PG-13.

Which means that any kid with a long leash and a little cash can go to the multiplex and see it, no questions asked.

No one - except perhaps Aaron Eckhart's character in Thank You for Smoking - is arguing that cigarettes are harmless, that smoking and cancer aren't connected. But maybe it's time that the studios, and its Washington, D.C., lobbying arm, the MPAA, stop dictating what is, and isn't, appropriate viewing for children and teens.

Maybe it's time people just grow up a bit and assume responsibility for their own lives.