LIKE MOST of you, I tend to make the majority of decisions in my life based on prejudice. It would be both exhausting, and eccentric, to think everything through from first principles, so most of us tend to rely on principles which have proved durable over time. Prejudices, in other words.

It’s a mistake to think that prejudices are inherently irrational, or automatically illiberal. In this country, as my colleague Tim Hames pointed out yesterday on this page, we have a deeply-rooted prejudice against having to justify ourselves to officialdom. Liberals such as Tim are therefore instinctively unhappy with the principle of identity cards, which compel the individual to account for himself to authority rather than the other way round. The same strain of liberal prejudice predisposes many of us to defend our common law traditions as a matter of instinct, leading us to shudder at the thought of an individual being detained without trial. A civil war was fought in this country after attempts to imprison people without a criminal charge being brought, and the bias against such an apparently arbitrary exercise of authority runs deep.

But I’ve been examining my prejudices recently, an exercise I recommend to all liberals. And I wonder if the time isn’t ripe for a review of some of our inherited biases. The great liberal economist John Maynard Keynes argued that when the facts changed he changed his mind. What do you do, he challenged his opponents. Well, the world has changed dramatically in the past three years, and my mind has changed too. I’m no longer anything like convinced that the liberal prejudice against ID cards, or incarceration without trial, is a wise presumption. And I’m no longer persuaded that the progressive consensus which denounces David Blunkett as an illiberal populist for rethinking our civil liberties is actually all that progressive.

It is understandable why the prejudice against giving the State the power to demand identity documents, or intern individuals, grew stronger in the 20th century. For most of the last century the greatest threat to an individual’s welfare, liberty, even life, was the abuse of state power. More people died at the hands of their own governments during the 20th century than by any other cause.

The 21st century is scarcely four years old, but already we know that there are greater threats to our welfare, liberty and life, at least in the West, than our own governments. After 9/11 we have no excuse for not recognising that terrorists now have the will, if not yet the potential, to cause slaughter on a horrendous and indiscriminate scale. Even before 9/11 we were having to come to terms in the West with the price to be paid for open economies, borders so porous that we were no longer able to determine just who had access to our societies.

The combination of large, unmonitored, migratory flows and international terrorism has placed huge burdens on those politicians charged with our security. I am not convinced that David Blunkett necessarily has the right answers. But I am increasingly exasperated with those civil libertarians who jeer at his proposals while refusing to recognise the problem and conspicuously failing to offer an alternative.

Of course, incarcerating individuals without trial is, as Winston Churchill put it, “in the highest degree odious”. But what should the Home Secretary do with foreign citizens whom the intelligence services have reasonable grounds to consider terrorist threats, but against whom it would be exceedingly difficult to proceed to trial? The Home Secretary has a duty to put our security above the sensitivities of foreign nationals. And the disclosure of prosecution evidence in criminal proceedings could help terrorists to disable intelligence networks, compromise informants and stymie counter-terrorism operations.

Those individuals whom the Home Secretary has interned in Belmarsh prison on security grounds are not chained in dungeons. They are free to leave this country at any point. What they are not, thankfully, at liberty to do is carry on consorting with terrorists in Britain.

The regime at Belmarsh is an imperfect solution to a complex problem — and so are ID cards. There seem to me to be a slew of practical concerns raised by the prospect of identity cards, from cost to the ability of a Government which has presided over so many computerisation cock-ups to produce a truly workable scheme. But there are real potential gains from ID cards in dealing with significant policy problems.

One of the Government’s greatest difficulties in managing migration is the difficulty in catching illegal migrants, whether they are asylum absconders, visa over-stayers or those who entered clandestinely. An ID card system would make it easier to identify those at liberty in this country who are here illegally. It would make it easier to deport those who have broken the law, easier to police access to services funded by the taxpayer and, by showing we could defend our borders, easier to defend the principle of managed migration.

Checking abuse of the asylum system could also help to choke off a route for terrorist activity. Past supporters of terrorism have chosen to claim asylum here, then disappeared from scrutiny the better to further their goals. Allowing the police to request ID papers would not, of course, stop terrorist activity, but it could play a significant part in frustrating it. The smaller the pool from which terrorists could be drawn, and the more difficult it is for them to move freely, the less the risk to our society. And the greater the chances of my family’s survival. Which is one thing I still have a very strong prejudice in favour of preserving.

michael.gove@thetimes.co.uk

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