From Clinton to Cook, we are happiest when our politicians are seducers. It's a complicated brew of envy and hypocrisy

My mother, who is now in her late seventies, always maintains that the most socially significant consequence of the Christine Keeler/Profumo affair in the early sixties was that it made talking about sex at dinner parties (in mixed company, in respectable society) possible. "Inappropriate" sexual liaisons were mixed with politics from the moment at which they became part of public social discourse.

For those too young to remember, the Profumo scandal was about a politician, a member of the government, having extramarital sex and lying about it - not under oath as it happens, but in the House of Commons which was much the same thing, in those sweet and far-ofttimes before the Belgrano sinking - inter alia - made it a perfectly acceptable political ploy.

My father, to my mother's annoyance, taught a 12-year-old me a "dirty" limerick about the business: "There was a young girl called Christine/Who shattered the Party machine./It isn't too rude/To lie in the nude/But to lie in the House is obscene." Shame, really, that it is hard to think of anything useful that rhymes with Monica.

Why is the sex life of politicians such a fascinating subject? Leave Bill Clinton aside for the moment. The Telegraph last week started a serialisation of a biography of Robin Cook: it gave two whole pages to its first extract - and was it about his childhood formation? Was it about his notable mishandling of the Queen's tour of India? Was it about his leadership ambitions? Of course not; it was about his sex life. As it happens his sex life is particularly dull (no cigars, no Chelsea strips, no stains). He was not particularly faithful to his wife of many years, who had a fairly high-powered job in the provinces. For the last four years in opposition he had an affair (clearly more than a sexual liaison) with his secretary, which was known to his friends, and to some extent to his wife, but was still moderately discreet. He was not conspicuous among those who spoke fervently of "family values" or the "sanctity of marriage". Shortly after he became Foreign Secretary he was outed by the press, and, forced to choose, chose a divorce and remarriage; after a brief and media-led kerfuffle he continued in his job.

This is a common enough story in a society which has no overarching problems with divorce. There is nothing in this that is criminal, there is nothing that is kinky, there is nothing that has any political implications at all. There is nothing in this that is interesting, actually.

Except that he is a senior government minister; a man with real political power.

If we want people to go on standing for public office, if we want people to desire political power, we had better work out quickly what is so sexually titillating about that power and what we are going to do about it.

The standard defence of this prurient fascination is that personal conduct says something important about public character: there is no point beyond which activities do not affect the whole personality and thence, by a sort of ripple effect, the personality's performance in apparently unrelated areas. This was the basic meaning of the feminist slogan "the personal is the political". A man who lies to his wife will lie in other circumstances. A woman who bullies her children will be a bully elsewhere. Or whatever. We have more than a right, we have a need to turn the spotlight on someone seeking our votes. We want to know who we are getting.

Put like this it makes good sense - the only way I can judge a person's likely future actions is by looking at their past: it is called taking up references and is considered sensible. If someone has not been a cabinet minister before it is not unreasonable to look at other areas of their life and try to calculate what sort of person they are as a way of guessing how they might behave.

However, it is not that simple. This is partly because of our modern sensibility which dictates that openness is an ultimate value and the opposite, "hypocrisy", a damnable sin. Therefore, anyone who tries to hide any aspect of their life is suspect.

A further complication arises out of our bizarrely confused notions of sexuality. We do not want to know about all aspects of a politician's life: what charities they support, for instance, or how much of the housework and child-raising they do. We want to know about their sex life, as though sexual proclivities give particular and uniquely accurate information about a person.

Moreover we seem to think that all sexual activity is evidence of moral weakness. Until the 19th century this was not the case. Sexual adventuring could be seen as proof of energy, charisma, persuasive power or a sort of glamour that was deemed appropriate for national leaders. George III was laughed at for the excessive domesticity of his life - "Farmer George" they called him, a staid, dull man. His son's libidinous carryings-on made him enormously popular, at least while he was young. It is hard to imagine crowds cheering Camilla Parker Bowles in the streets of London because her liaison with the present Prince of Wales means that he is behaving in a princely, noble and virile way.

One reason for this sea change in public mood is the bourgeois model of marriage that we have adopted. A couple who marry for contractual (dynastic or otherwise) purposes may be more easily forgiven if their sexual desires turn out to be divergent. A modern couple freely choose each other to meet their individual sexual and emotional needs, and thus can be seen as showing bad judgement in selecting someone to whom they cannot be faithful.

Another reason why we might expect different behaviour from our public figures than people used to, is because we have invented a moral concept called privacy. For vast swathes of human history isolation was the great threat, not invasion of privacy.

Until well into the 18th century, people slept together, ate together, gave birth and died in company. People comfortably belched, farted and even urinated in public rooms; they waved sheets out of windows after wedding nights; a proof of importance was to bath, sleep and rest in public. While social class was stable, everyone knowing their place, privacy was not necessary. In a bourgeois culture, however, lines need to be drawn. Pas devant les domestiques would have been meaningless to a medieval aristocrat; it makes crucial sense to a household establishing who are servants and who are bosses. Hot running water and flush toilets are commodities in need of use - I am rich enough to be able to bath on my own, therefore to bath on my own has value. The Industrial Revolution accelerated the process, and new boundaries were quickly established. When Henry Mayhew published his social survey London Labour and the London Poor (1851-62) his intentions were humanitarian, but a large part of his distress was driven by personal disgust: the poor were doing in public what the better-off had chosen to make private - eating, drinking, socialising and attending to bodily needs on the street rather than in the privacy of the family's domestic space.

Not surprisingly at this point Romanticism constructed individualism and privacy as moral and aesthetic values. Women are confined to the home as a symbol of their purity; and sexuality becomes intensely personal, private and secret. There is a necessary split between public services and domestic and sexual life.

We are currently concerned about invasions of privacy and what sort of privacy is appropriate for people whose work lives are public; but we tend to do this without a consciousness that privacy is itself a social construction and a comparatively modern one at that.

But, above all, I believe that the reason we are so intent on exposing the sexual peccadilloes of our leaders is because we are peculiarly sheepish about the relationship between sex and power.

Power is sexy. In this era of continual photographic exposure and and television coverage, the way politicians look is crucially important. They have to be attractive - they have to have something that compels, demands, involves their constituents. One of the strongest criticisms of John Major was that he was "grey" - not dynamic, not sexy. Politicians like Clinton who run on a broadly populist platform particularly have to match our aspirations - and most of us want to have more, and more exciting, sex than we are getting. We sexually invest in our politicians and, since we are not open about this, we are easily prey to sexual curiosity, moralistic judgement and complicated thwarted desires; their sexual downfall meets a real psychological need.

Power, frankly, turns heterosexual women on. Political power requires of men many of the same personality traits that seduction does. The sorts of men who seek political power will often be the sorts of men who respond actively to sexuality. Far from being surprised that male politicians have highly active sex lives we should accept that in our present cultural climate this is very probable. This is not a new phenomenon; what is new is that we have added to the complicated tensions of this relationship the new desire for telling all, for an absence of repression and suppression. We demand to know what we don't want to deal with.

It's time to grow up. If we want to know everything our political leaders get up to and we don't want them to get up to sex then we shall simply have to elect women. For, while male power appears to excite women, female power terrifies men. So we don't elect sexy women - can you think of a sexual scandal in the working life of any elected woman politician? It would be simpler to come out to ourselves about the immature way we still treat sexuality repressed, envious, sly and self-righteous. The biggest criticism of Clinton is that he should have been a competent enough politician to have worked this out in advance.

BILL GREENWELL

Miserable Guy with apologies to Rodgers & Hammerstein

I expect every cock in the henhouse to mock My roaring repentance of sin in romance And they'll cluck that they're vexed at my biblical texts Adding ribald remarks about opening my pants - For I'm so ashamed to reveal The sights that made Monica squeal...