"I felt I was the lamb to the slaughter," Diana Spencer told a friend the night before her wedding in 1981, according to the journalist Andrew Morton. I suppose this imagery is unavoidable now, as one thinks of that frail and bloody body gasping for oxygen in a Paris tunnel. But it is also, surely, the deepest truth about Diana, and the central reason for the startling grief of the last week. Diana's life followed a sacrificial trajectory. She was offered up to the twin gods of monarchy and celebrity. They made for a brutal combination.

Diana was just 19 years old when she was corralled into the royal family, blithely unaware of her role in an ancient cycle of dynastic realpolitik. It is now a commonplace that there is no mystery left to royalty, but this profound secret—of the manipulation by Charles and the Queen of a young girl for the propagation of the royal species—was known only to a tiny few at the time. Reasons of state demanded it. "I am not a political figure," Diana insisted in one of her charitable speeches, but, of course, she was. The monarchy's pretense to be apolitical is in itself a shrewd political stance; and without the connection to monarchy Diana would have been an unknown debutante in a minor aristocratic family. The Crown needed an heir; and it needed a boost. Diana gave them more than they bargained for.

From the beginning, she represented a mixed blessing to the Palace. The post-abdication monarchy's game plan was, in Weberian terms, to depend on traditional authority to defend its power. After Edward VIII, it was clear that any other strategy was as volatile as it was unconstitutional. So the stuttering George VI and canny Queen Mother improvised a monarchical banality in the 1940s; and the bland and dowdy Elizabeth, so much her father's daughter, made passivity her modus operandi. Diana's impeccable lineage, her sublime Englishness, her coy reticence, seemed perfect for the continuance of this strategy. But the Crown made a fatal misjudgment. What it did not reckon on was Diana's charismatic power, her gift to mesmerize and captivate, to tap into the iconic strength of monarchy itself, to revive a royal tradition as deep as it is explosive.

You could see it in that first, famous photo. The young kindergarten teacher in the English garden, cradling an infant as the evening sunlight caught her hair and bestowed almost a halo on the new royal persona. And also a sexuality: the light lit through her dress, outlining a lithe, virginal form. Perhaps no royal member since Elizabeth I created a regal iconography of such sensual power, or subliminally trapped us into an enduring fascination with her glamour.

In the country that was once a center of Marian devotion, the combination of female sanctity and male authority has always been a potent brew. Victoria tapped it; Thatcher rode it; but Diana brought raw physical beauty into the mix, transforming the monarchy instantly into a global, fully modern phenomenon. From the moment that became clear, it was also clear that Diana's version of the monarchy was in direct conflict with the Windsors'. She threatened the twentieth century monarchy at its foundation, supplanting the passivity that was its essential protective coloring with an electric and overpowering aura. Where the Queen stuffily sought international power through the archaic and faintly comic contraption of the Commonwealth, Diana instantly commanded it through the new global media. She began to wield a power that could only further marginalize an already weakened institution.

So the Windsors set out to destroy her. It is hard to know when she first intuited this; and the knowledge must have been confused with her anger at her cold, adulterous husband. But she did come to see the dynamic clearly in time, and became, as Tina Brown put it, the mouse that roared. Where the Windsors were provincial, stiff and withdrawn, Diana was cosmopolitan, tactile and ubiquitous. Where they understood the traditional notions of reticence, hypocrisy and facade, Diana lived and breathed the modern air of authenticity, honesty and confession. Falteringly, but unmistakably, she grew to understand her own power and her own charm, and took greater and greater risks in expressing them. The unassuming English rosebud slowly unfolded into an Oprahfied, American bloom. In recent months, she had moved even further: royal but without the restraints of royalty, she touched the boundaries of policy, fusing popular culture with a political edge that came close to redefining monarchy. The contrast with the introverted, neurotic Charles, fretting over old flames and old buildings, was yawning.

But, as Elizabeth II must have reflected, the Diana strategy carried enormous risks. The constitutional demands of monarchy were one thing; the price of celebrity another. Between them, Diana was subject to intolerable pressure. Her strength was that the press and the Crown desperately needed—as well as envied—her. Her weakness was that she was a human being, who actually needed love and comfort and family, and who was made, by the hounding of the media and indifference of the royals, increasingly desperate. Her solution, a post-monarchical, post-national celebrityhood, was an ingenious one. Part of the tragedy of her death, I think, is that we will never see whether it could finally have worked. And whether it could have revived the monarchy, or finally proved its superfluity.

Her funeral, in its majesty and scale and aura, will be contrasted most clearly with Churchill's. The British have not felt such grief since. But with Churchill, the funeral was in some ways a burial of the past, a final farewell to the nineteenth-century giant who saved the country in the twentieth. Diana cannot, of course, compare to Churchill. But her young death points in exactly the opposite direction and is therefore more poignant. In Britain, she was more than a celebrity. Her royalty struck a deeper and more significant chord of national identity. She was a symbol of humanity in the midst of artifice, modernity in the heart of tradition, spontaneity in a country where ritual is often a substitute for life. Diana, in her coy and tortured way, was a passionate advocate of life before ritual. That is why she affected the British so deeply and why, perhaps, the crowds that massed in the days after her death were so disproportionately composed of the young. She represented a new kind of England, one that could break through the tradition and class and history that too often impede the more human needs of integrity and happiness. As I have tried to understand why the news has sent me into a kind of gnawing and deepening sadness these last few days, I can only offer this partial explanation. In burying Diana, the British have done more than bury a princess. In some way, we have buried a future.