BRISTOL PALIN looked downright radiant on the set of NBC's "Today Show" yesterday with her chubby-cheeked infant son resting on her lap.

She seemed so happy. Even as Matt Lauer interviewed her, she couldn't seem to stop gazing down at Tripp's angelic face as he slept. It was an idyllic image - the beautiful, young mother and 4-month-old baby, with doting granddad, Todd Palin, sitting nearby.

I believe Bristol was genuinely trying to warn teen parents away from the travails of early parenthood by talking with Lauer about the late-night feedings and diaper changes. But the unspoken message was: See this adorable baby? You get it by having unprotected sex the way I did with Levi Johnston. And everything turned out OK.

Of course those words didn't come out of her mouth, but that could very well be kids' takeaway message. That's what troubles me about Bristol's high-profile media tour.

It must have been a heady experience for an 18-year-old, more accustomed to being in the background of her mother, Alaska Gov. Sarah Palin, the former Republican vice presidential nominee. But this time, it was all about Bristol. Later in the day, she walked the red carpet with Hayden Panettiere of NBC's "Heroes," before participating in a town-hall meeting sponsored by the Candies Foundation for National Teen Pregnancy Awareness Day. Flashbulbs popped and photographers shouted, "Bristol! Bristol! Over here!"

A recent study by Oxygen showed that 25 percent of women ages 18 to 34 would rather win Tyra Banks' "America's Top Model" competition than the Nobel Peace Prize. And here was teen mom Bristol, enjoying the kind of attention usually reserved for celebrities. It definitely beats flipping burgers back in Wasilla.

It's certainly a mixed message for impressionable minds.

On one hand, you have Bristol, the new anti-teen mom role model, discussing her regrets about becoming an early parent. But she looked none the worse for the experience.

Bristol's new gig as a teen ambassador with the foundation could wind up becoming a first step in a public-speaking career. A book on teen parenting could follow. And who knows what else? Maybe a mother-son line of clothing.

"By missing school and doing TV appearances, Bristol Palin is not setting a good example for teenage moms," said Cara Gardenswartz, a clinical psychologist based in Beverly Hills, and an expert with momlogic.com.

Bristol's "do-as-I-say, not-as-I-did" message is confusing - not to mention ineffective.

For instance, when parents use drugs but tell their children not to, the parents' actions override their words, Gardenswartz pointed out. "In addition, promoting abstinence has not shown to be effective in preventing teen pregnancies. In fact, encouraging safe and protected sex amongst teens having intercourse has been proven useful," she said in an e-mail.

At least this time around, Bristol's talking up abstinence instead of dismissing it as "unrealistic" as she did in a Fox interview earlier this year. The baby's semi-estranged father, Levi Johnston, also resurfaced yesterday on CBS and praised abstinence as well.

"But I also think you need to enforce, you know, condoms and birth control and other things like that to have safe sex," he pointed out. "I don't just think telling young kids, 'You can't have sex,' . . . it's not going to work."

Both Johnston and Bristol are living proof of that. *