Personally, I blame Celine Dion

When James Cameron's movie Titanic was first released in this country, a friend invited me to go and see it. "Don't you want to know what happens?" he asked in (I hope) mock-incredulity when I refused. I said I was prepared to go only if he could promise that the liner would miss the iceberg and dock safely in New York, where one of the passengers would go on to found an early version of Microsoft. That really would have defied audience expectations, instead of turning one of the great maritime disasters into a sentimental upstairs-downstairs love story.

When James Cameron's movie Titanic was first released in this country, a friend invited me to go and see it. "Don't you want to know what happens?" he asked in (I hope) mock-incredulity when I refused. I said I was prepared to go only if he could promise that the liner would miss the iceberg and dock safely in New York, where one of the passengers would go on to found an early version of Microsoft. That really would have defied audience expectations, instead of turning one of the great maritime disasters into a sentimental upstairs-downstairs love story.

Since then, the theme tune of Cameron's version of the catastrophe has become one of the most frequently requested pieces of music at funerals, which suggests that a surprising number of people spend their last moments fantasising about going down with the ship. (Or that they like Celine Dion, which is harder to forgive.) Now all those people who still haven't had enough Titanic will be able to go along to the Science Museum in London and take part in an interactive experience, including the opportunity to touch an iceberg and discover the little-known scientific fact that it's cold.

At one level, this is merely further evidence of the grip the disaster continues to have on the public imagination. Films and exhibitions about the Titanic come round with monotonous regularity, adding nothing to the known facts and prompting little discussion about why some historical events metamorphose into cultural myths. Why does the loss of this ship attract so much more attention than the Aberfan disaster, whose child victims would surely exert an equally powerful tug on audiences' heart-strings? And if there is something distasteful about the very idea of a Hollywood treatment of that catastrophe, why don't the same reservations apply to a tragedy at sea in which many more people lost their lives?

A simple answer is that some events are too recent to take liberties with. Cameron got away with fictionalising the loss of the Titanic, but he would face an outcry from survivors if he did the same to the Zeebrugge ferry disaster. In the same way, there have been Jack the Ripper walks in the East End of London for years, but no attempt (as yet) to take people on conducted tours of the sites in the north of England where Peter Sutcliffe mutilated his victims. This distinction is particularly revealing, for the crimes committed by the Whitechapel murderer were no less gruesome than those of the so-called Yorkshire Ripper. Yet "Jack" has become a ghoulish tourist attraction, a bogyman to provide bored visitors to London with cheap thrills, while Sutcliffe is still regarded with horror.

As terrible events recede into history, they lose some of their emotional charge, becoming transformed into a species of costume drama. That is certainly the trajectory of movie versions of the Titanic, which have shifted from the documentary-style realism of Kenneth More in A Night To Remember (1958) to the completely fictional romance of Kate Winslet (below) and Leonardo DiCaprio in Cameron's blockbuster. It also suggests that some historical tragedies just aren't tragic enough for Hollywood, which inserted a doomed romance into From Hell, the latest movie treatment of Jack the Ripper.

I seem to be in a minority in finding this process nauseating, not to mention an insult to the people who actually suffered and died. (I know novelists and dramatists have always used real events as inspiration, but it's not as if we're talking Shakespeare here.)

How much time needs to pass, I wonder, before the Holocaust becomes fair game for a concentration-camp love story? The Science Museum's exhibition panders to another questionable idea, already tried out in one or two Holocaust museums: that people need to identify with individual victims if their sympathy and interest is to remain engaged.

Visitors to the Titanic experience won't actually be thrown into tanks of freezing water in a darkened room and left to drown, which would be taking the quest for authenticity a bit far. But they will be handed a facsimile of the original White Star boarding pass bearing the name of a passenger as they go in. At the end, they will discover whether "their" card-holder survived – and presumably, in the case of the ship's most celebrated passenger, Kate Winslet, whether she eventually recovered from her doomed shipboard romance and found love in the arms of a glamorous movie director.