The chilling scenes at Gatwick Airport yesterday only emphasise that Britain is right to be in a state of terrorist alert.

A man was arrested under the Prevention of Terrorism Act during an operation when the north terminal had to be closed.

There has been criticism of the Government for its high security measures around airports in general and Heathrow in particular over the past two days.

But if there had been no increase in security and a terrorist attack had taken place, there would have been justified outrage at official inaction.

Police and top Government officials were acting on strong intelligence reports that some sort of attack was imminent.

It's wrong to suggest that such a step would be taken to bolster support for the Government's unpopular stance on Iraq and in any case, heightened security would change few minds.

Whether or not there is a war against Iraq, the threat to Britain and other western countries from fundamentalist terrorists is likely to continue.

As September 11 proved in America, they will stop at nothing to achieve their appalling aim of destroying those who dare to disagree with them.

Everyone must be vigilant, particularly at likely targets such as airports and shopping centres, to prevent any attacks.

But people should, as far as possible, go about their normal lives. If they do not, the terrorists will have achieved a victory without using a single bomb or bullet.