But in modern Europe, the reality has recently been less highly charged. There is little sinister about the daily use of ID cards in railway stations and post offices. If anything, they make the queues move faster; most view them with benign indifference.

But with David Blunkett's announcement this week that Britain is to start introducing a national identity card scheme, the debate over the erosion of civil liberties was reactivated.

Mr Blunkett says an ID card system would help tackle crime, illegal employment, immigration abuse, ID fraud, and terrorism. His opponents warn of bureaucratic chaos and a creeping infringement of traditional freedoms.

One by one over the last century, the governments of most EU member states have already had these arguments and taken the decision to introduce the cards. Twelve countries - but not the UK, Ireland and Denmark - have already adopted some form of ID card scheme.

Austria, Finland, France, Italy, Luxembourg, the Netherlands, Portugal and Sweden have made ID cards voluntary; Belgium, Germany, Greece and Spain require citizens to carry the ID with them at all times.

For the Home Office, the largely sanguine approach of most EU citizens may offer some encouragement; but in other areas the picture is less reassuring.

Repression

There is little hard evidence of the card helping in the fight against crime, illegal immigration and fraud. Furthermore, many countries report that it has become associated with police abuses and repression of minority groups. There is also growing concern about the increasing sophistication of the cards, as governments update what was once a simple paper document into an electronic collection of personal information and biometric data - eye and fingerprint scans.

ID cards have been around in Belgium since 1919, and are an uncontroversial part of life for anyone over 12. "For me it's normal to carry a card. We have it in our wallets like money," says Marleen De Keyser, a receptionist.

Since their introduction in Greece during the 1940s, most have viewed them as an integral part of their national identity - even though the police have the right to demand them, and do so frequently.

French identity cards have been present in some form since the 19th century. About 51% of the population uses them, and an official at the human rights group the Ligue des Droits de l'Homme says the debate over their existence is "a polemic which is now obsolete".

Their popularity is perhaps even greater in Italy, with the cards welcomed as a counter to the country's labyrinthine bureaucracy. Although not compulsory, they allow their carriers to travel across EU borders, identify themselves at police checkpoints, receive state health services, qualify for elections and prove their age. "There are few things in Italy that seem to work," said one Italian diplomat, Giuseppe Mistretta, earlier this year. "But our citizens seem satisfied with the ID card - which is rarer than sex with an elephant."

British opponents of the scheme say biometrics and database technology are not yet foolproof, and errors could lead to dangerous confusions of identities.

But such moves have already begun on the continent, relatively smoothly. Italy began to experiment with electronic cards in 2001, and their mass introduction is due to begin in May next year.

There has been little complaint in Italy, or in Spain, which has also announced the introduction of microchips in cards.

Even so, civil liberties campaigners are uncomfortable. Statewatch, a European civil liberties monitoring group, fears that data may one day be gathered into one huge database - similar to the Schengen information system in Strasbourg, which holds files on 1.3 million individuals, mainly for immigration purposes.

The organisation also points to several initiatives, such as the EU health card - due to be introduced as early as 2005 - as possible precursors to an EU-wide ID system. This card will give the holder access to free medical treatment anywhere in the EU, but also looks likely to store a wealth of biometric and personal data.

Each European country will be free to choose whether to include records of treatment received, photographs, and biometric data. Campaigners say it may eventually become an all-in-one ID card, passport, national insurance card, bank card and driver's licence.

Technology

The historical associations of compulsory ID systems also trigger unease. In the Netherlands, where a new type of ID card was introduced in 2001, the issue revived memories of the German occupation - the first time the Dutch were obliged to carry proof of their identity. The occupying Germans used the cards to identify Jews - many of whom were later killed in concentration camps.

Another concern is the abuse of the system by police forces. There is evidence in continental Europe that members of ethnic minorities are asked to provide ID more often than other citizens.

Mouloud Aounit, the secretary general of the French anti-racism group MRAP, says of the cards: "They aren't in themselves a force for repression, but in the current climate of security hysteria they facilitate it... Young people of Algerian or Moroccan descent are being checked six times a day."

Michel Tubiana, the president of the human rights federation FIDH, agrees: "A system which allows ID checks encourages discrimination."

On the crucial question of reducing crime and illegal immigration, the necessary statistics do not exist. The evidence is anecdotal.

In Belgium, Bart Vansevenant, of Ubizen, the company behind newly introduced digital technology, says the system is useful in fighting illegal immigration.

"The police can just stop anyone in the street and ask for ID," he says. "If you're in the country illegally and you can't produce a card, then it's simple - you're illegal."

German officials also believe that the recent inclusion of biometric data - approved by MPs in response to the September 11 attacks - has increased national security. "It's safer, quicker, and more foolproof," one senior official said.

Wolf-Dieter Narr, one of Germany's leading human rights activists, counters that the real purpose of the cards is more sinister, and has uneasy echoes of the past - to keep certain groups out of Europe.

"As a guy who grew up in Nazi Germany, I think it is very important we don't discriminate against any kind of people," he says. "They are trying to use it to strengthen the European castle against all kinds of foreigners."

EU partners planning a smart card for all things

The ID card of the future could replace the traditional passport and driving licence and serve as a cash card for tax payments. It will contain chips containing personal and biometric information such as scans of fingerprints or irises.

In Italy the new documents look like credit cards. Personal information is stored in an "optical memory strip" and in a microchip. Individuals have the option to include health and financial information on the card's digital record. Ultimately the plan is that the cards will have multiple functions.

The new Spanish model is billed as the world's first internet ID card. The first one will be issued early next year. By sticking their card into a reader attached to their computer, people will be able to apply for a passport from home or do other official business with the state or local administration.

In Germany, from 2006 new ID cards are likely to include a digital photo of the holder as well as his or her fingerprints, similar to what David Blunkett is proposing for Britain.

In Belgium, a new card, in use in 11 cities, includes a smart chip with the holder's digital signature and an authentication certificate. It will let Belgians access many government services.