IN the long and bitter battle against an enemy who would stop at nothing, they were accepted with a resigned shrug of the shoulders.

Along with blackouts and ration books, identity cards were just another restriction on freedom.

And the years since the end of the Second World War have seen a number of attempts to re-introduce them, the perceived solution to all manner of social problems - from rising crime to football hooliganism. All have so far failed, squashed under the twin objections of the difficulties of operating an ID card scheme and the threat to civil liberty.

But now, as Britain prepares for a new war, this time against the evil of terrorism, the momentum in favour of cards is gathering pace, and could prove unstoppable. Home Secretary David Blunkett said ID cards were being given a "high priority" in the wake of the September 11 attacks, and that beating terror must take precedence over freedom.

And opinion polls suggest more than eight out of ten Britons are in favour of ID cards. Such is the national mood of horror and determination to take action against terrorists, that sacrificing a few civil liberties seems to be a small price to pay for security.

The police have traditionally been among the keenest advocates of ID cards, as a tool to help the fight against crime. The Association of Chief Police Officers backs the idea in principle, although it would need to see details of how a scheme would work, according to a spokesman.

"If the Government was to introduce ID cards, for safety and security, that is something we would go along with," he says. "If the police were suspicious of somebody, they could be asked to produce their identity card. It would be a way of verifying somebody's identity, and that would be useful for the police.

"People would not be stopped randomly. If somebody is stopped or arrested, then the usual procedure is to ask their identity, and cards would be a way of doing that, although there are a lot of details that haven't been worked out yet."

The Police Federation, which represents rank-and-file officers, has backed the introduction of ID cards for the last eight years. "It should be on a voluntary basis to start with, and if that doesn't work it maybe should be made mandatory," says a spokesman.

"It will help to cut down the number of people taken to police stations just for the purposes of verifying identification. It will also help to stop fraud, especially benefit fraud, as well as cutting down on bogus callers. It is also a valuable proof of age for pubs and clubs and cinemas."

He says objections that civil liberties would be eroded by ID cards overlook the fact that a variation on the scheme is already effectively in place, and pale beside the need to take greater precautions against terrorism.

"Most people carry identification in some form or another, from driving licences to credit cards and bus passes," he says. "And, in view of all the security alerts, and the attacks in New York and Washington, our security is going to be tightened up, and ID cards would help."

But the suggestion that ID cards could stop terrorist attacks is dismissed by Dr Colin Clark, lecturer in sociology and social policy at Newcastle University, who sees them as an excuse by authoritarian tendencies to cut civil liberties back still further.

"If we had ID cards, would this stop someone flying a plane into a building? Of course not," he says. "I would need to be convinced of the merits of an identity card system and what it would do to improve security, because I'm not sure it would do anything. The bottom line is ID cards would not have stopped the events of September 11.

"This debate over ID cards has cropped up time after time over the last 20 or 30 years, and it would be rather opportunistic to go down this route in the light of what happened in America. And there are real concerns from a civil liberties point of view, about the way information is used, who generates it and who stores it."

He rejects the suggestion that only people with something to hide have something to worry about with ID cards. "Even if you don't have anything to hide, you have a lot to be scared about. If the government has this information on you, it can be used in a variety of different ways, sometimes without your knowledge and against your interests."

And, he says, ID cards are another example of increasing interference in our everyday freedoms. "The French philosopher Michel Foucault said government was a monitoring and surveillance machine, and ID cards would be the next step in that. You can't walk down the street without being recorded by CCTV.

'It is not the card itself, it is the information behind it, that is stored on a database. Who has access to it? Can it be hacked into? What if they made a mistake? There are a lot of valid questions about ID cards."

But for Alisdair Gillespie, senior lecturer in criminal justice at Teesside University, the dangers of an ID card are less apparent. But then, so are the benefits.

"It is harmless and it is useless, but it has got the potential to be useful and harmful," he says. "The argument for them is that they allow the police an added opportunity to identify people.

"But we know how easy it is to forge banknotes, and there has got to be the question of how difficult it would be for a terrorist organisation to forge ID cards. One of the big arguments against them is that they are just untenable. But I'm not sure how many people would object to them, given that most of us carry identification anyway, in driving licences and other ID cards."

For civil liberties campaigners, he says, one fear is that the card could be used to carry confidential information, which would be available to anyone with access to the appropriate equipment. Storing medical information on the card would be useful for accident victims, but we may not want those details falling into the hands of strangers.

"Another problem is what is going to happen if you don't carry it?" he says. "I don't want to get hauled into police custody every time I forget my card. But then what is the point of having it, because the criminal is just going to say he forgot it?"

In the end, the benefits identity cards might bring in terms of any greater security have to be offset by the possible dangers lurking within that small bit of plastic.

"Yes we want to be safe, but do we also want to live in a prison camp?" says Mr Gillespie. "The danger is, this situation could give politicians a pretty good excuse to do something the public would normally not let them get away with.

"It is window dressing. The public demand action, and when we keep being told we're the next target, identity cards are an easy thing to do without making any difference. I think they reassure the public but I'm not sure they do any good whatsoever."