Being "sexy" has become the most important accolade a teenager can aspire to, outdoing intelligence, success at school and character.
This, at least, is the view of American author Carol Liebau, whose new book Prude: How The Sex-Obsessed Culture Damages Girls is shortly due to be published in Britain.
Liebau brings heavyweight credentials to her mission.
She's the first female editor of the Harvard Law Review, and as such, she's cracked another glass ceiling on the road to female equality.
She also happens to be incredibly attractive into the bargain: this is no old-fashioned blue stocking attacking a generation out of envy for a life which had passed her by.
Her book, I believe, is a timely wakeup call to us all. "Girls are being led to believe that they're in control when it comes to sexual relationships," Liebau says.
"But they're actually living in a profoundly anti-feminist landscape where girls compete for attention on the basis of how much they're prepared to do sexually for boys."
Even much of the so-called "good" advice aimed at girls is bad, insists Liebau. Sexual education in schools starts with the assumption that all teenagers are having sex, and does little to encourage abstinence.
She goes on to quote Sharon Stone and some of the most laughably bad advice ever given to teenagers. Stone, it appears, encourages teenagers who feel pressured to have sex to offer oral sex instead, since it's safer.
"Young people talk to me about what to do if they're being pressed for sex," she says. "I tell them what I believe . . . if you're in a situation where you cannot get out of sex, offer oral sex."
But it is not just Stone who dishes out bad advice. Liebau also blames celebrities such as Paris Hilton, Christina Aguilera and Britney Spears for the phenomenon.
Sharon Stone: Advocates oral sex if you cannot get out of sex
Looking at Hilton's websites, which feature films and photographs of her in provocative and dominant poses, the message she sends out is clear: Young women are being taught to believe that "sexy" equates to empowerment and that only through promiscuity and sexual aggression will they achieve their peers' admiration.
Dr Michele Elliott, director of the children's charity Kidscape, told me that what is going on is rushing the sexual development of children to the point where it is dangerous.
"Girls as young as five or six are wearing thongs that say 'Eye Candy' and T- shirts which say 'So many boys, so little time'," she says.
"You can buy pole-dancing kits for kids, and I've known parents who take their children to beauty salons for make- overs.
"Children are told about looking stylish on a first date, or given advice about diets. We're raising a generation who believe this is what they should be aspiring to."
Two years ago, I made a documentary about women and age, in which I spoke to women in their 50s who were being made redundant from their jobs. The same wasn't happening to men of equivalent age and status.
Their problems stemmed from fading looks in a culture which all too often prizes beauty above ability.
It was depressing, but not as bad as an interview I also conducted with a group of pretty 11-year-olds in West London.
They all wore make-up and trendy clothes and said they'd be happy to have plastic surgery.
It was, they said, more important to them to be good looking than it was to be clever, helpful or talented. Looks, they believed, were the passport to success.
They all spoke of having boyfriends, and their nods, winks and giggles indicated to me that while they might not yet be having full-blown sex, this was certainly not long in the future.
Carol Liebau believes this sudden drop in the age at which girls have sex is the most noteworthy aspect of the sexual revolution.
She quotes a report at San Diego University that analysed 530 studies of sexual behaviour spanning five decades and involved 250,000 young people.
Liebau blames celebrities like Britney Spears for young women's distorted view of female empowerment
From 1943 to 1999 the average age of girls losing their virginity dropped from 19 to 15. During the same period, the number of sexually active women under the age of 20 rose from 13 per cent to 47 per cent.
And between 1969 and 1993, the percentage of female teenagers and young adults having oral sex skyrocketed from 42 to 71 per cent.
But perhaps the most dramatic phenomenon was the revolution in young women's beliefs about pre-marital sex. Only 12 per cent approved of it in 1943.
By 1999, 73 per cent did. Liebau notes: "Baby-boomers first had sex when they were in college. Today's young women lose their virginity when they're still at school."
And it's not only an American problem. A recent Unicef survey of 21 countries found that British children were most likely to have had sex before the age of 15.
Sexually transmitted infections in Britain have risen by 63 per cent in a decade, with HIV and gonorrhoea close to record levels.
"There exists a status quo in which almost everything seems focused on what's going on below the waist," argues Liebau.
Typing the word sexy into Google, I found a staggering 22,800,000 entries versus just over 4,000,000 for the word clever.
Clothes are marketed to make you look "sexy"; food is "sexy", as are cars, cameras, and certain kinds of table lamps.
Even Gordon Brown is not immune. On June 15, 2004, the BBC business programme heralded his achievement of becoming the UK's longest continuously serving Chancellor with the words: "But never mind that: he's a brooding malcontent who oozes sex appeal."
Checking further into our politicians revealed that "sex and David Cameron" yielded 458,000 entries.
From all of this, just one message emerges. Sex is everywhere. Everyone is doing it. That's the way it is.
Sex has become just another commodity, something to drop into your day between a visit to the manicurist or a trip to the supermarket.
The very real psychological, emotional and physical impact on young girls of having too much too soon is being ignored.
By relentlessly emphasising sex and beauty, the standards by which young women have traditionally been valued - their character, intellect or skills - are being eroded.
Our increasingly sexual society also affects the way young girls look at being mothers.
Of course, unwed mothers were treated deplorably in the past, but today's almost universal acceptance of pre-marital sex has effectively sanctioned a life-changing decision that can have a severely detrimental impact on a young unwed mother and her child.
The psychological and spiritual costs to young girls living in a sex-saturated society can't be calculated in physical or economic terms alone.
Giving "too much, too soon" has been associated with an increased risk of suicide and a much greater incidence of depression.
How ironic that in so many other ways young women have never had it so good. Their professional options are virtually limitless.
There are more female medical and law students than male ones. In school, girls out-perform boys. They start reading earlier.
They live longer, are less likely to commit crimes or become victims of them.
Even that last bastion, pay scales, was toppled earlier this year when a survey from the private banking group Investec revealed that 39 per cent of women who work full-time and have partners believe that they earn more than their men.
Translated into numbers, that means that 1.8 million women in full-time work across the country earn more than their partners.
But as barriers to female professional advancement have fallen, so too have many of the traditional social conventions that protected girls.
When I was a teenager (and indeed, until I was in my late 20s) if a boyfriend came to stay at my parents' house, he always had to sleep in the spare room.
Too many of us, it seems, have forgotten that those well-worn customs (requiring a boy to meet a girl's parents before a first date, for example) are, in fact, a way of protecting a daughter and being actively involved in her development.
From the boy's side, turning up in the living room to meet the parents - however embarrassing - signaled a readiness to assume responsibility for the daughter of the house.
Such customs sent out signals not only of sexual restraint, but also of a proper respect for women.
Many of the customs that today are dismissed as limiting and restrictive were actually very empowering, because they offered women a way to resist unwelcome sexual advances ("I can't - my parents expect me home by midnight") without having to look prudish or frigid.
Nowadays, girls who resist a boy's advances are no longer backed up by a social consensus which honours their right to say "no", their right to be chaste.
Parents themselves have fallen foul of the fashion which seems to dictate that everyone should be allowed to do what they want, when they want.
And, as a result, everything around today's young girls conspires to push them towards sex, sending the implacable message that the sexually inexperienced are uncool, abnormal or hopelessly undesirable.
And as society has changed, so too have role models. Where once younger people looked up to leaders in their communities for their inspiration, now they look to celebrities such as Paris Hilton and take their cues from her and her like.
Since Paris's main message seems to be one of "just do it", those who don't want to are inevitably left looking hopelessly out of touch with the rest of society.
And what this has created, it seems to me, is a world where men are freely able to exploit women and get away with it.
Take the current crop of teenage men's magazines: most are openly hostile to women, seeing them as nothing more than sex objects for the delight of macho men.
Yet women willingly send in their (half-naked) photos to be pored over by thousands of insecure young men who are only too anxious to return to a world where men did rule the roost and women were merely chattels.
Thirty five years ago, when I co-founded Spare Rib - one of the earliest feminist magazines - the debate about female sexuality was one of the trickiest the feminists encountered.
Like my co-founder, Marsha Rowe, I'd been working on an underground magazine at the end of the 1960s.
The underground Press had an ambivalent attitude towards women. To refuse to sleep with someone was both old-fashioned and hypocritical in a culture which promoted free love.
Marsha and I both felt uncomfortable. How could real liberation - the right to work, to achieve, to earn the same as men - be equated with having to have sex with someone you didn't necessarily love?
It didn't. And that conviction was one of the impetuses which kicked the magazine into life. The same is true today, where overtly raunchy sex is the new chic among today's teenagers, seen as a further step along the road to liberation.
Sexuality is a wonderful part of being human, but it is one that should not be treated lightly, or as a commodity devoid of emotional power.
It's high time that grown-ups started taking an interest in what their children get up to: benign neglect may be considered a "liberated" way to rear our children, but in the end it is our daughters who will pay the price.
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