Stop tittering in the back of the class, there.

It's often said that a huge amount of traffic on the internet is caused by pornography, and I've no reason to doubt it. This means that, not yet fifty years after the sexual revolution, access to pornography is pretty much ubiquitous in our society. Views on this are divergent and shadowy because the issue isn't much talked about; consumers of pornography aren't very willing to stand up and defend it, and its critics are formed of a bizarre alliance of feminists and conservatives, i.e. people who are in favour of traditional family roles that the feminists are not.

A huge shift has occurred in the way women relate to men and society over the last one hundred years, and it hit in essentially two ways. The first was the sexual revolution, which finally gave women control over their own reproductive process through the advent of the birth control pill, and involved a lot of changing social mores about female sexuality. The other was feminism, which sought to systematically remove inequalities between men and women in society. One was about liberty, the other equality: uneasy bedfellows.

Pornography really started to spread in the 1960s as a result of the sexual revolution, and it was initially welcomed by many feminists. We have to remember just how repressive mores concerning female sexuality have been for most of recorded history, not least in the 1950s; for a lot of feminists during the first flush of the sexual revolution, it was seen as wrong to oppose any expression of female sexuality. That included pornography. And pornography, of course, was opposed by exactly the people that the advocates of the sexual revolution were fighting against - the "family values" conservatives - and this helped it get seen as a good thing.

But then gradually, as feminism developed, a big disagreement broke out. Pornography is produced and consumed almost exclusively by men, and there's a very strong argument which says that it really amounts to the exploitation of female sexuality for male purposes - just another facet of domination. Even worse, it eroticizes this domination. And so the anti-pornography movement was born, and even Germaine Greer - who had touted promiscuity as a route to liberation - pointed out that clearly not all expressions of female sexuality are automatically liberating, and some could reinforce the unequal position of women in society.

In the 1970s and 1980s this led to a rather large rift in the feminist movement that is sometimes known as the "Porn Wars". Feminists like Andrea Dworkin began to press for ordinances against pornography in cities in the U.S. and in Canada and clothed themselves in the rhetoric of traditional conservatives, whereas their opponents claimed to be standing up for free speech and a woman's right to dispose of her sexuality as she wished. And so, though it is hardly possible to imagine an organized group of men shameless enough to lobby for their right to consume pornography, a group of feminists essentially did the job for them by lobbying for the right for women to participate in pornography if they so wished.

And it is in this vacuum between liberty and equality that pornography continues to exist today. The biggest publication in the feminist world in the last few years has been Ariel Levy's Female Chauvinist Pigs, which claims that many women are complicit in the project of objectifying themselves and so reinforcing harmful gender stereotypes. Levy says there is a "raunch culture" in America, encouraged by icons like Paris Hilton, who encourage women to demean themselves for male purposes; and she reserves criticism for so-called "lipstick feminists" who she alleges equate empowerment with leveraging their sexuality to control men. Little need to explain where pornography lies in her view.

Indeed, the general terms of the debate about pornography remain the same. Arguments abound about the impact of pornography on people's behaviour, or "family values", or on people's ability to form healthy sexual relationships. But an attempt to censor pornography on the basis of the fact it is grotesque and demeaning to women will never succeed, however true it may be, because this would reek of legislating morality and "modesty"; and isn't that what decades of female empowerment have been trying to overthrow?

Meanwhile, a generation of young men and women are growing up in a culture saturated with pornography and the values and view of sex that it encourages.