Mr. Morgan was no less foreboding, though his worries about Ms. Markle are more general. He went so far as to invoke Wallis Simpson, the American divorcée whose love affair with King Edward VIII prompted him to abdicate the British throne. Ms. Simpson died in 1986, but she remains one of the most hated people in Britain.
“If Meghan has got a couple of kids and decides to take them back to California,” he said, “she will make Wallis Simpson look like a tea party.”
But the wedding is almost upon us. The day will be given over to bodices and bustles and edible flowers, a medieval spectacle shot through with an electric current of sex. Prince Harry and Ms. Markle are still in the first flush of genuine attraction, as anyone with access to a television can attest. (Compare those images to the 1981 interview of his parents, in which Prince Charles, asked if he was in love with Diana, responded, “Whatever ‘in love’ means.”)
The monarchy needs this charisma badly. By the late 1990s, ordinary Britons felt increasingly alienated from a “privileged, inward-looking, inbred royal family that was obviously dysfunctional,” said Mark Leonard, co-author of a 1998 report that recommended swift and comprehensive modernization.
The royal family instituted new policies in an effort to keep up with the times, decommissioning the royal yacht and declaring that the queen would begin paying taxes. But it is the rise of Diana’s sons — telegenic and more tethered to the world of ordinary Britons — that has been its salvation.
When she arrives at St. George’s Chapel at Windsor Castle on Saturday on the arm of her mother, Meghan Markle will represent the latest of these changes. She has shuttered her blog and social media accounts, with their traces of deeply held opinion.
Colleagues say she is fiercely disciplined on the set, intent on saying every line as it is written on the page. But she is also the girl whose childhood bedroom, her biographer wrote, featured a poster of Rosie the Riveter, sleeve rolled up and bicep flexed, under the motto “We Can Do It!” This is the role she has been preparing for all her life.