You would have to go back to the era in which Dickens was an international hero to find anything comparable. Yet Harry Potter novels have become more like hit singles than books, with people queuing to buy the latest must-have consumer item, and his author filling the Albert Hall like a rock-star, not an author. So huge is her fame and fortune that even the most envious authors now see Rowling’s career as a curse, bringing with it the need for rock-star style security at her house in Edinburgh, a secluded estate in Scotland and a bodyguard for her daughter Jessica. The poor, lonely single mother is now one of the richest people in England, married to a doctor and the mother of a son but she is still, from the point of view of the literary community a sport of nature. At the Queen’s party for the British Book World at Buckingham Palace last year, there were only two people famous authors and editors hesitated to talk to: the Queen, and JK Rowling.

This is a great pity, for before Harry appeared there was a justifiable fear that future generations, hypnotised by computer games, would no longer discover the magic of books. Rowling has saved every author, teacher, bookseller and librarian from possible oblivion, and children’s publishing from marginalisation. The long wait for the fifth novel has transformed the fortunes of other superb children’s writers, from Philip Pullman and Eva Ibbotson to newcomers such as Louisa Young and Mark Haddon. It has rescued the fortunes of failing toy train manufacturers Hornby with a miniature version of the Hogwarts Express; made specs smart; and even bolstered the applications to British public schools.

Perhaps the oddest aspect of Rowling’s success is that while the posters and media hype may impress adults, children who adore the books tend to despise the hype and merchandising surrounding them. Unlike the success of Eoin Colfer’s Artemis Fowl, Anthony Horowitz’s Alex Rider spy series or Meg Cabot’s The Princess Diaries, her success was achieved initially by word of mouth, and by focusing entirely on the quality of the novels. Rowling created a world that, with its jokes and anxieties, dangers and rewards, most children instantly recognise as their own.

Other children’s writers, most notably Jill Murphy, Ursula le Guin and Diana Wynne Jones had the idea of a school for witches or wizards, but none described it in such depth and detail. Critics such as Robert McCrum and Anthony Holden have sneered at her style, which, though occasionally repetitious is in fact admirably clear, and direct. The efforts of Warner Bros, in fact, merely supply the details of Hogwarts children can’t quite imagine. Equally, her use of myth and legend is far more intelligent and original than that of CS Lewis. Not since E.Nesbit, in fact, has an adult recreated a child’s inner world with such clarity. What pupil has not dreamt of escaping out of school grounds by means of an Invisibility Cloak and going to the best sweet-shop in the world; or of petty playground feuds that are serious and deadly? Nor are Harry’s struggles without an objective correlative. The evil followers of Lord Voldemort, who believe in “pure blood” wizards, echo the beliefs of the Nazis. The good, led by Dumbledore, display tolerance, humility and a sense of humour. Philip Hensher claimed in The Spectator that she satirised New Labour: though party politics seemed to seep into the last novel, her agenda is demonstrably more liberal and humanist than that. If Harry, like Luke Skywalker or Tintin, is a little too good to be true there are the comic sidekicks Ron and Hermione to make him three dimensional, and the dreadful Dursleys to make his holidays miserable. He is the descendent of every reluctant hero in literature, from King Arthur to Bilbo Baggins, and those who attempt to yoke him to their cause, whether astrological or political, or to denigrate him as nerdy and middlebrow, look foolish.

Children, as Philip Pullman has said, ask big questions about the world they live in, and authors envious of Rowling should consider whether they do the same. Through Harry, children learn that life-sucking depression (the Dementors) can be repulsed by concentrating on a single happy memory; that capital punishment is abhorrent because you can, as in The Prisoner of Azkaban, pick the wrong person as a murderer; that friendship is worth more than riches or power. In each novel, Harry has been confronted with one of the seven deadly sins: avarice, pride, wrath and envy have so far been resisted, leaving gluttony, sloth and what one imagines will be the final temptation for a teenaged boy, lust, still to come. Although The Prisoner of Azkaban has been the most perfectly conceived and executed of the series so far, each novel has deepened and darkened the moral choices to come. Small wonder that Rowling has taken a three-years break after a killing output of writing a book a year. To me that, more than anything else, is the hall-mark of a real writer, who is as passionate about reading books, and enjoying life, as she is by writing them.

The Independent on Sunday June 2003