It is tempting to imagine that Gordon Brown has personal reasons for wanting ID cards no longer to be compulsory. When he is forced to make a dash for the rear door of 10 Downing Street next May or June, perhaps he is planning to lie low for a bit, have some plastic surgery and then reinvent himself under an assumed name, possibly as a genial school teacher in somewhere like East Kilbride.

But I doubt whether the Prime Minister or Alan Johnson, the new Home Secretary, are really any less keen on ID cards than they were when trying to make out that the things an essential weapon in the war against terror. Yesterday’s announcement has political expedience written all over it: the Government realises that the Conservatives’ policy of abolishing ID cards will turn out to be very popular, and knows that the electorate will rebel at the prospect of having to cough up £100 just to prove they officially exist.

No one should read anything into Mr Johnson’s promise that the cards “will never be compulsory”. Maybe the Government really has dropped the idea of sending the identity police round to our homes to hit us with £1,000 fines for failing to produce one of these wretched things, but you can be sure that once they exist, the Government will seek to make them effectively compulsory, by preventing us doing all manner of things if we can’t produce one.

You want to claim unemployment benefit? Sorry, sir, where’s your ID card. You want to take your children swimming at the municipal baths? Sorry, sir, but under child-protection rules we are obliged to check the ID of everyone entering these premises against the sex offenders register.

The Government is still pressing ahead with the national identity register, to which will be added the details of everyone who applies for a passport. Anyone on the register will be obliged subsequently to inform the authorities of a change of address, under pain of a £1,000 fine. In other words, if you don’t want to carry a card, that’s your choice. But we are still going to take your fingerprints, and if you don’t have a card we can march you down to the station to have you checked.

If there was ever a solution in search of a problem, it is ID cards and the identity register. You know what will happen: the authorities will spend thousands of hours pursuing forgetful, peripatetic students. Meanwhile, al-Qaeda sleepers diligently settling down to lives as teaching assistants as they prepare suicide attacks will be careful to conform to all pettifogging bureaucracy. Like the Tube bombers before them, it isn’t their identities they wish to conceal, only their ambitions.

Ross Clark ID cards voluntary? Don’t you believe it

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