Fleet Street, as we still call ourselves, had a lot of fun with the takeover of Express Newspapers by Richard Desmond. Tee-hee, the publisher of Asian Babes and Readers' Wives had bought Beaverbrook's old moral crusader. True, the Express itself had become a new Labour sheet edited by Rosie Boycott, a veteran feminist, and the company did publish the Daily Star, a randy red top. Nevertheless, the arrival of Desmond was still a good laugh. Sancho Panza had unhorsed Don Quixote and suddenly the crusader's sword meant something quite different. We laughed because the standard hack joke is the subversion of high-mindedness and pomposity. Desmond managed to do this twice - first, by overthrowing Beaverbrook's right-wing, middle-class moralism and, second, by affronting Boycott's new-left, middle-class moralism.

What was odd was that it all seemed to be no more than a joke. People were amused but not upset that a national newspaper had been bought with soft-porn millions. Once it would have been a national scandal, but not now. Why? Because nobody is really upset by porn any more. It has, as a commodity, been utterly normalised.

The extent of this normalisation process is seldom appreciated, though the evidence is all around us. Advertising and mainstream television now carry images that, a few years ago, could have been seen only in porn magazines or videos. Cars are sold on the basis that "size matters" and the hugely successful "middle-shelf" lads' mags sell celebrity soft porn as an aspect of an idealised male lifestyle. This is essentially a repackaging of porn for a new generation - to be seen buying and reading Penthouse or Asian Babes may be just too middle-aged and uncool, indicative of repression, whereas Loaded and FHM are cool, and hip.

This pervasive soft porn has made the legal suppression of hardcore in the UK seem anomalous. Why, if we can have this above the counter, should we not have what we like below the counter? Andreas Whittam Smith, the chairman of the British Board of Film Classification, has recently suggested there should be a sex shop in every town. This would enable provincial customers to buy the near- hardcore R18 videos currently only easily available in licensed big-city sex shops.

Whittam Smith is plainly heading towards the view that censorship should only be a protective and regulatory system, not an absolute sanction against the freedom for adults to see and do what they like in private. But the grossest anomaly of all is the internet. Every conceivable variety of pornography is now instantly and freely available online and - though this fact is often disputed by evangelists for the industry - it is clear that the vast majority of internet "hits" are on porn sites. No national or local qualms can resist this flood of material; the internet, by definition, crosses all frontiers. And, with the sole exception of child pornography, as Gary Glitter discovered, few law enforcers are interested in pursuing what must now be the biggest wave of mass criminality in history. It simply can't be done. On the basis that laws that the people don't obey are bad laws, then surely the laws against hard porn should now be abandoned.

But, first, we should ask ourselves a question: why has all this happened? The first answer is the American constitution. In 1997, the US Supreme Court ruled that porn on the internet could not be regulated by Congress because it was protected under the First Amendment, which guarantees freedom of speech.

Obscenity can still be prosecuted, but, in practice, this is never taken to mean explicitly sexual material. Since America overwhelmingly dominates the internet, this means that the Supreme Court has decided that hard porn be made globally available.

At around $10bn a year, porn revenues in the US are now bigger than Hollywood's domestic box office receipts and larger than the revenues of the rock and country music industries combined. The growth - largely linked to videos - has been explosive. And this is now a very respectable business: almost every American hotel, for example, now offers hard-porn TV channels to its guests. But, even if we assume the indifference of the Supreme Court to such considerations, it is hard to ignore the oddity of a ruling that defines pornography as speech. The judges came down on one side of an argument that had largely taken place within feminism. Some feminists - notably Andrea Dworkin and Catherine MacKinnon - had argued for the banning of pornography on the basis that it was not simply speech, but action. Like racist or sexist abuse, it had real effects in the real world, in that it promoted violence against, and contempt for, women.

Other feminists argued that this was to confuse expression and action. Pornography is expression and, far from being exploitative, it is liberating. Nina Hartley (a stage name), for example, is a radical feminist who has appeared in more than 300 hardcore films, in order to show that "a woman can be strong and sexually autonomous". "For all the lip-service we give to sex being holy and wonderful and spiritual," she has said, "we let Madison Avenue use it to sell spark plugs and dishwashing detergent - to sell anything but sex." In other words, it is difficult to argue for the specialness and privacy of sex, when it is clear that society at large has already abandoned any such ideas and accepted it as an aspect of trade. In effect, the Supreme Court concurred and normalised global hardcore.

Liberation meant freedom from repression, and carried with it a utopian ideal of an utterly free society in which the sexual appetite was as easily satisfied as any other. Sexual frustration and maybe even perversion would be banished, for they were the creations of the bad faith imposed by repressive institutions. This is a persuasive idea that has long outlived the Sixties. Indeed, in a recent book, the screenwriter Matthew Chapman wrote: "every time Jerry Falwell or the Pope opens his mouth to preach, another pervert is created".

The underlying theory is a hydraulic view of sex that owes something to a crude reading of Freud. The sexual urge is seen as a kind of pressurised fluid that needs a safety valve if it is not to damage the individual and, by extension, society. Porn is just one such valve. In fact, as anybody who has trawled the erotic exotica available on the net will testify, it doesn't work. In spite of the material being absolutely freely available, straight, "healthy" sex is a minority offering. Perversions predominate, from bondage to she-males and from Japanese schoolgirls to lactating women. This is plainly liberation of a sort, but it is not the back-to-nature liberation implied by the Sixties utopians.

It is indicative, rather, of how porn-ography is a self-generating addiction: the more you have, the more you want. There is no simple fluid to be released; rather, there is an urge to be constantly stimulated and the more it is stimulated, the more variety it seeks. Or, to put it another way, it is easy to imagine a sexually contented person in a non-pornographic society; it is much harder to imagine one in a pornographic society. This much, I think, is self-evident. Nevertheless, it can be argued that this form of excitement will, in time, pall.

Rather surprisingly, this has been suggested by Larry Flynt, the American publisher of Hustler magazine, whose wars with censorship were made into a movie. He has argued that relaxing of the obscenity laws throughout the US would reduce the size of the sex industry simply because people would grow bored. He is supported by evidence from Denmark, where a removal of the obscenity laws in 1969 led first to a sharp rise, but then to a long slow decline, in the porn industry. Danish porn now makes its living out of exports to less liberal countries.

This is not convincing, however, mainly because it is hard to believe there are any meaningful restrictions left in the US and because the phenomenon of the internet seems to have created an entirely new demand for new forms of sexual stimulation. People who had never before thought to worship women's feet now appear to be doing so, for example. But if porn is not to pall and if the hydraulic-release view of sex is wrong - which it plainly is - then we seem to be heading for a society with ever-increasing levels of explicit erotic imagery. New legal restrictions are unlikely and, in the global context, probably unworkable.

What will be the outcome? It seems plain to me that, if you do not believe in a simple safety-valve view of porn, then it is almost impossible not to agree, at least in principle, with MacKinnon and Dworkin. Although it may not be true that porn is always an exploitation of women, it is certainly true that it is no more a form of speech than is the sale of addictive drugs. It is, contrary to the US Supreme Court judgement, a definite act in the world, with cer- tain consequences. Those consequences may foster the promotion of sexual crime - it is hard to separate cause from effect in this area - but they will certainly diminish the value of human life. Porn reifies and instrumentalises the body, separating it from the self. It presents sex as a release sought from the world by a predatory appetite.

This is the opposite of the sacred, private, intimate view of sex as the encounter of the vulnerable self with another. It is, in fact, this sacred view of sex upon which our culture is built. Without it, love, marriage and almost any other form of human commitment would be incomprehensible. It is hard to imagine any great work of art that does not, in some way, refer back to sex and sexual love as absolutes.

In these terms, pornography is a very great evil indeed, a subversion that strikes at the heart of human value. That people still feel queasy and ashamed of consuming porn in public is indicative of the still-persistent awareness that there is something wrong here, that modesty is being breached, that something is being exposed that should be left hidden and that the self of the consumer is being compromised in some shameful way.

On the strength and survival of that awareness depends the possibility of a society less sickeningly pornographic than the one we are rapidly becoming - and even, perhaps, the possibility that someone, somewhere might at least raise more than a smirk when a national newspaper is bought by the publisher of Asian Babes.

See Joan Bakewell