That she was beautiful is clear — Princess Diana's beauty was frozen in time by her untimely death.
"A less attractive girl — we wouldn't be sitting here talking about her now," said Tina Brown, who has been covering Diana since she was a young editor at Britain's saucy Tatler magazine.
"Everyone ended up falling for her charm," Brown said. "When she turned her full beaming effect on you, it was pretty devastating."
Brown's new book, "The Diana Chronicles," has spent the last nine weeks on The New York Times best-seller list.
She says that before Diana came onto the scene in 1980, "The royal family had become a stale commodity. ... There was a sense that this family needed a new act."
That new act arrived in the person of Diana Spencer, whom Brown describes as "fresh, young, beautiful, well-pedigreed, absolutely flawless background, no past that anybody could rake over."
Brown says the British public saw a chance for the monarchy to be re-invented. "The nation went crazy," she said. "They went for it, as did the royal family. — They wanted that fairy story as much as the public did."
But Brown says it didn't take long before the fairy tale ended. She says Prince Charles began to feel jealous of his very popular princess, about two years after they wed, right after Prince William was born, when the family went on their first official trip to Australia.
"Everywhere they would go, there were two lines," said Brown. "Charles would go down one line, and Diana the other; the side that got Charles would groan, and the side of Diana, everybody cheered and went crazy."
"After a time, that gets old, and in the end, Prince Charles felt very overlooked, very hurt, very left out. He didn't have the self-confidence or the secure nature of his manhood, in a way to accept that Diana, forevermore, was going to eclipse him."
But, according to Brown, Diana was insecure herself, and despite her soaring popularity, was crumbling in private. Suffering from both postpartum depression and bulimia, Diana soon discovered that Charles had resumed his relationship with his old lover Camilla Parker-Bowles.
Diana did not find much sympathy from her new family.
"The royal family thought Diana was big, big trouble. They wanted her to just calm down and become one of the team," said Brown. "Times like when the queen went to open Parliament — that's her big day. Diana had a new hairdo. The papers went crazy. Princess Margaret said, 'How dare she have a new updo when you're going to open the houses of Parliament?' This is the kind of thing that Diana had to deal with."
After 14 years — and infidelity on both sides — Diana and Charles' marriage was ruptured beyond repair. In 1995, Diana sat down for an interview on the BBC's "Panorama" program with Martin Bashir — then with the BBC, now the co-anchor of "Nightline." Diana famously told Bashir, "There were three of us in this marriage."
"If her goal was to somehow keep a relationship with the royal family and be a detached princess with the queen's blessing, it was an act of absolute suicide," said Brown.