There has been a conspiracy over the Roswell incident, says William Hartston, but not in the way most people seem to think
Fifty years ago yesterday, something happened in the town of Roswell, New Mexico. Since that date - American Independence Day in 1947 - the United States government and security services have conspired to cover up the truth. And the truth is that there are no such things as flying saucers, no aliens have ever landed in Roswell, their bodies have not been preserved in secret government locations, their technology has not been borrowed for US military purposes and no Americans have been abducted by visitors from other planets.

All the evidence suggests that this has been perhaps the most brilliantly effective post-war disinformation campaign by the American security services. By persistently denying the existence of flying saucers, and even denying the existence of evidence to show that they are interested in them, the CIA has fuelled the imagination of Ufologists and conspiracy theorists to the extent that most Americans now believe that little grey men with smooth skins and no eyebrows have been day-tripping to California.

"There's an enormous amount of evidence from all over the world to show that governments have indeed covered up the truth," said Stanton Friedman, the world's leading authority on the strange happenings at Roswell. "The United States certainly has. We have statements about hundreds of documents about UFOs that are being withheld." And when, under the Freedom of Information Act, he finally obtained some 900 pages of material whose very existence had been denied, many of the pages had vast areas blacked out. What more conclusive evidence of a cover-up could there be?

He is right. There has been a cover-up. But not in the direction he and millions of other Ufologists and fellow space-travellers think. Let's go back to that crash in 1947. Just suppose it was part of some top secret US military research. There must have been, and must still be, many strange things going on in the skies that the US government does not want anyone to know about. When something went wrong, it was a gift from the skies when good American citizens started jumping up and down saying they had seen a flying saucer. Belief in flying saucers was the perfect foil to deflect attention from defence secrets. Far better that investigative efforts should be channelled into looking for alien bodies than that they should probe the inner mysteries of the Defence Department.

So the US Air Force, the CIA and the FBI went into overdrive, doing what they do best: they denied it. Which, of course, made more people believe it. So they concocted a story about weather balloons, which made even more people believe they must be lying. After 50 years of denials, they are clearly on a roll. According to one recent survey, the number of Americans who have been abducted by aliens could be as high as 2 million. (That figure comes from asking people about bumps and noises experienced at night. Apparently if you wake up in a different position from the one you fell asleep in, or if your pyjamas are crumpled, it could be because you were abducted by aliens and returned clumsily to your bed. They're brilliant at probing our minds and levitating us through walls, but putting our jim-jams back on straight is beyond them.)

Last week, the official US government explanation of the happenings at Roswell confirmed the existence of mannequins dropped as crash dummies in the area. The historical evidence, however, confirms that such dummies were not dropped until the 1950s. Which proves - in the minds of true believers at least - that whatever dropped in 1947 must have been a grey chap with no eyebrows.

Soon, I confidently expect, another document will be dragged reluctantly from CIA top secret files under the orders of a judge under the Freedom of Information Act. It will appear something like this:

Twinkle xxxxxxxx xxxxxxxxxxxxx

xxxxxxxx wonder xxxxx you are

xxxx above the world xxxxxxxxxxx

xxxxxxxxxxxxxxxxxxxx in the sky.

And once again the Ufo-lovers will find their case proven beyond doubt.

Last week a television programme in this country debated the question of whether aliens had landed on earth. In a phone-in vote at the end of the programme, a startling 92 per cent of respondents said they believed that aliens were already here. Three cheers for the Security Services of the USA.