Philip Hensher: One couple's happiness will not translate into national self-esteem

The unavoidable notion that a royal wedding is somehow related to the mood of the nation is impossible to date back beyond the late 19th century

(Darren Diss)

We seem confused about the meaning of "commoner". Kate Middleton, we are told, will be "the first commoner to marry an heir presumptive [sic] to the throne in more than 350 years". But when Lady Diana Spencer married the Prince of Wales in 1981, she too was described as "the first commoner" – meaning non-royal – to marry the heir to the throne in centuries. Confusion over what William is – heir presumptive or apparent? – and what we should call him – William Wales? Prince William? William Windsor? – was already bad enough. Now we don't know what his bride-to-be is, or when the last time one of her happened, if ever.

The whole confusion is suggestive of a certain nervousness around the wedding. In his classic, The English Constitution, Walter Bagehot wrote that "a princely marriage is the brilliant edition of a universal fact and, as such, rivets mankind". (Expect to see a lot more of this line in the months to come.) But what happens if the universal fact stops being a simple, shared, experience which we all understand? Marriage, since Bagehot's day – even since Prince William's father's day – has changed immensely. What we aim at in our marriages has altered beyond recognition, let alone what we actually achieve.

There hasn't been a memorable English royal wedding since the festival of vulgarity which was the Duke and Duchess of York's 1986 extravaganza. Following closely on the wedding of the Prince and Princess of Wales in 1981, the two state occasions seemed, in their tone, to define the decade. The sheer excess of Diana's meringue dress was one thing; the Duchess of York's grinning progress down the aisle in a confection lavishly embroidered – it was said – with helicopters another. There was Grace Kelly in the congregation at the Waleses'; Dame Edna Everage in full purple wig in the audience – the only word – at the Yorks'. If the crowd underneath Buckingham Palace took to bellowing for a kiss from the newly wed Waleses in 1981, the Duchess of York was happy to whoop up the crowd at the same point, like a warm-up act at Live Aid. The 1980s somehow coagulated at these two moments. The Waleses' wedding was a first blast of excess, sentiment, kitsch ceremonialism and royalty-as-showbiz; 1986 is the year of the helicopter, whether in the outward emblem of the Yorks' passion, embarrassingly enshrined in the worst of Ted Hughes's laureate epithalamiums, or, in the January of that year, at the centre of the most shameful episode of Mrs Thatcher's government, the Westland affair.

These brilliant editions of the universal fact scooped up the age and presented them, in a festive day, in ways which were glamorous at the time, but, as glamour tends to, quite quickly came to seem mildly humiliating. Since then, members of the Royal Family have gone on getting married – the Earl of Wessex, Lord Linley, and, for real trainspotters, Princess Anne's son Peter Phillips. All have been deliberately quiet affairs. None has made a statement, or presented a glass we can inspect our sometimes ugly aspirations in.

The unavoidable and accurate notion that a royal wedding is somehow related to the mood of the nation is, like most constitutionally mystic notions, impossible to date back beyond the late 19th century. The succession of princely marriages which Victoria's children embarked upon were treated, largely, with the sort of respect and public splendour which earlier ages would have found very odd. The beanfeast of the Prince of Wales's wedding to the Danish Alexandra – "Sea-king's daughter from over the sea!" as Tennyson wrote – was followed by a similar sequence. It was designed to make Victoria, in the contemporary phrase, Grandmother of Europe as well as Empress of India and a quarter of the globe beside. Public respect, on each occasion, was unalloyed.

It was very different in earlier ages. The indecent haste with which the ageing sons of George III sought brides after the death of the Prince Regent's daughter greatly amused Regency society, if anything. The Prince Regent's marriage to a dirty and garrulous German princess, Caroline of Brunswick, had inspired no patriotic fervour or romance about the terrible Caroline. (Lord Malmesbury had to tell her that she should be very well washed "all over", and years later, a servant bluntly told a House of Lords committee inquiring into her behaviour with men friends that she "was very fond of fucking".)

Only after Victoria's children was a royal wedding an overheated public event which told us something about our national state of mind, whether the Duke of York's to Elizabeth Bowes-Lyon, the austerity-defying splendour of the present Queen's in 1947, Princess Margaret's chic marriage to a café-society photographer, or even Princess Anne's to someone of much the same social standing as the Middletons today.

There is no chance of keeping Prince William's wedding a quiet affair. Probably there should be no attempt to. But sycophantic talk of the young couple's "modernity" disguises the fact that the "universal fact" of marriage has changed beyond recognition in recent years. The heir to the heir to the throne has no chance, any longer, of presenting his marriage as an ideal version of something most of us will, at some point, undertake.

In the year Prince William's aunt, Princess Anne, married for the first time, 1972, the number of weddings in Britain hit an all-time high at 426,241. By 2008, the number had sunk to 232,990. That is the lowest number of weddings since 1895. There was, too, by then, the interesting innovation of 7,169 civil partnerships adding to the total. That interesting innovation is only one of the ways in which the "universal fact" has diverged and become incapable of a single representation. You might add, for instance, the enormous increase in the number of people, such as the Leader of the Opposition, who choose to settle down and have children without marrying. I would guess, too, that in the popular mind the notion of a truly opulent wedding has shifted from the 1981 Wales spectacular to the entertainments of a Hinduja or a Mittal nuptial. The weddings of the children of some Indian billionaires have been reported as costing upwards of $55m. Does anyone care more about a prematurely balding great-grandson of the last Emperor of India and his pretty young wife than about the people who run India?

As the weirdly fascinated coverage of the Wales engagement across the world has shown, the answer, it seems, is yes: plenty of people still do. When the wedding takes place, the nervousness will recede, and for a moment, we will kid ourselves, just as we did in 1981, that one couple's happiness can translate into ease and solid self-esteem in the minds of a whole country. That is quite a large burden to place on anyone, and even the strongest supporters of the royal wedding were reduced, this week, to ludicrous cost-benefit analyses demonstrating that the royal wedding could be worth £1bn to the tourist industry and "the manufacturers of memorabilia". That is one way to justify it. Another is to realise, at this moment, that the whole business will slowly, but inevitably turn from patriotic, sentimental fervour on the day into acute embarrassment in years to come. That would benefit everyone.