Then came the fax: visa request refused. You may well be wondering what I had been planning to lecture on. The scandalous rate of female infanticide in Asia, perhaps? But no, my brief was to talk about the position of women in the West. And the title I chose for my lecture will give you an idea of the post-modern trajectory I am now on. "The Strange Case of Madonna - of Belle de Jour II". We are talking Cultural Studies.
My starting point was to have been this: am I alone in detecting a growing resemblance between Diana, the Princess of Wales, and the pop star Madonna? Are they by any chance related? I have thought for some time that we should be told. But the answer is not that they are related. No: literally, if not metaphorically, there are in fact the same person!
Now I know this may strike seasoned royal-watchers as somewhat improbable. I am sorry to say that Piers Morgan has shown no interest whatever in my claim, despite its obvious potential as a scoop for his new soaraway Daily Mirror.
And I can see why. Ten years ago, it would have been hard to think of two women more diametrically different. In 1977, when Madonna Ciccone was posing nude for Penthouse, Diana Spencer was being awarded the Miss Clark Lawrence Service Prize for ladylike conduct at West Heath School. Three years later, when Madonna was strutting her stuff in seedy Manhattan nightclubs, Diana was doing the gay gordons at Balmoral. While the one was hurtling to stardom with albums like Madonna and Like a Virgin, the other was producing baby boys. Looking back a decade, the gulf between the Material Girl and the Maternal Girl seemed unbridgeable.
Yet all this time - this is where my allusion to the film Belle de Jour comes in - the two roles were in fact being played by one woman. Or, if you insist on being literal-minded, let us say that these two apparently opposing female images were in truth merely two sides of the same cultural icon.
For me the moment of revelation came in 1986, the year Madonna attempted to launch herself as a movie star in Shanghai Surprise. She cut a rather forlorn and talentless figure, I remember thinking, not unlike the Princess of Wales in her first film, Westminster Wedding. But what really convinced me was Diana's extraordinary appearance on stage at Covent Garden, dancing with Wayne Sleep to Billy Joel's "Uptown Girl". Where was Madonna that night?
Since that unforgettable night, the evidence has steadily accumulated. First, there was their mutual interest in that most fashionable of showbiz good causes, Aids. Then there were the simultaneous marital crises, precipitated by dangerous liaisons with dashing cads (I can't even remember - was it Diana or Madonna who kept on phoning up Warren Beatty?)
And then came the two bestsellers: Madonna's Sex and Diana's True Story (originally to have been called No Sex). To cap it all, rumours began to circulate that Diana was planning to go over to Rome - or back over, as it was from Catholicism that the crucifix-wearing Madonna had originally lapsed.
How long, I found myself wondering last year, before the long-awaited release of In Bed with Diana?
If you are still not persuaded, I recommend that you simply compare two recent photographs of the two. When Diana returned this week from New York, the Times naively asked if she had borrowed the singer's hairdresser and tortoise-shell sunglasses. Fools! They completely missed the unmistakable bulging biceps which Madonna has developed by pumping iron every day in her gym.
What is the significance of this extraordinary - but apparently diminishing - schizophrenia? How are we to interpret the gradual absorption of the demure young bride by the muscular man-eater? Can it be that it symbolises a paradigm-shift in the definition of female identity? Is the age-old antithesis between virgin and whore - housewife and prostitute - finally succumbing to the dialectical process? Is Madonna the synthesis of the two?
You know, some American universities will pay serious money for this sort of thing. Is it really too late to reconsider my visa application, Deng?
Miles Kington is away.