SEX and politics go together in this country. We aren't taken by the one without the other. Plain, sauce-free politics is for the serious minded, but stir in a dash of something extra-marital and everyone is interested.

Just take this week. The Labour Party conference has skirted such weighty issues as whether or not to bomb Iraq, or whether it is a good investment to build schools and hospitals under the private finance initiative (a sort of never-never higher purchase scheme, under which the State buys now and carries on paying over the odds for the next 30 years).

But no, the headlines have belonged to an affair in the 1980s between two consenting adults. This four-year liaison between a government whip and a junior government minister has everyone hooked, at least until the next eye-popping distraction.

The reason is simple and now known to us all: before he became Prime Minister, John Major spent four years having illicit sex with Edwina Currie. Even now, I almost have to write those words again, just to make sure.

Some political affairs are more surprising than others, although none these days is likely to have the impact of the Profumo Affair in the Sixties, in which sex, deception and State secrets led to the resignation of Conservative MP John Profumo.

It seems to be a Tory failing, what with David Mellor's three-month fling with Antonia de Sancha or Tory minister Rod Richards' affair that caused him to be sacked by that figure of rectitude, John Major. Or Piers Merchant, the Tory MP and family man who strayed towards his 17-year-old political assistant.

Yet Labour politicians have wandered too, most notably Dennis Skinner, who travelled, in headline terms, from being the Beast of Bolsover to the "beast of leg-over". And didn't Labour MP Ron Brown once take a shower in the Commons with a woman friend?

The Currie and Major affair has a number of telling details, some quite disturbing. Edwina's chat-up lines are said to have included the Carry On-esque: "Would you like to see my Peak District?" Another favourite was: "Would you like to come up and see my manifesto?"

Personally, I'd have thought that a prudent answer to both questions was a hurried "no" said while sprinting towards the nearest door.

Aside from the prurient details, and the unexpected mental task of re-casting John Major in terms of lasciviousness, the revelation of this well-hidden affair illustrates again how much we like a political sex scandal. For us the Gallic shrug of indifference that allowed President Mitterand to maintain a wife and a mistress just won't do. We want our moral indignation and we want it now.

And how much more satisfying that the politician retrospectively caught with his pin-stripes down should be John Major, the grey man of politics who used to drone on about "back to basics" and Victorian values. If sometimes he seemed on edge, we now know why: he must have been terrified of exposure. No Prime Minister wants an old take-away Currie habit to be discovered. And no voter wants to find they have been lectured to by a lecher.

It is difficult to feel much sympathy for either party in this dalliance, while acknowledging that these things happen, both in and out of politics. Major sang a dull hymn in praise of old-fashioned values, while having shameful secrets of his own. And Currie, well she has a book to sell and has stirred up the most satisfying dust-storm of publicity imaginable.

For all that, the Tory virulence unleashed at Edwina Currie - "cheap trollop" "a bitch" and "ghastly woman" are some of the acid drops spat in her direction - seems conveniently to forget that two people were involved in this affair.

Updated: 12:40 Thursday, October 03, 2002