There is a part of me that pities a state snooper. Imagine spying on me. Much as I might wish it otherwise, my life is not, in fact, a hectic round of glamorous covert naughtiness and super-cool subversion. I am not in nightly secret contact with my global anarcho-syndicalist fight-the-power (weekends only) posse. Frankly, it's all a bit dull, as the dog has sometimes had cause to mention.

Equally, imagine - if you can imagine - prowling through the average Briton's text messages. AM STUCK ON TRAIN AGAIN. MUST BRING DOWN GUVMINT. B*STURDS. And does anyone really join MI5 for the chance to peek at the emails of people complaining to Amazon because their Elbow CD hasn't turned up? What do you learn about global terrorism when you can estimate the precise number of individuals surfing cost-comparison sites in an effort to knock a bit off the car insurance?

Then there are telephones. It must be a sort of nervous reaction to a life in journalism, but I loathe the devil's instrument. Anyone who gets better than a Yup or a Nope out of me - if I have even bothered to answer a call that was not expected or pre-arranged - has received my equivalent of the Gettysburg Address. I don't do chat. I never have any gossip. I take forever to text (a quaint insistence on punctuation might have something to do with it) and I have no interest in an electronic tagging device that allows me to take bad photographs while whizzing around the web listening to horribly compressed music tracks.

Other people are different, I know, but for an actively intrusive state that surely poses its own problems. There are, of course, people out there, a very few, who are emailing mad plots and talking in code on their phones. Most of the rest, millions of them, just blether. Relentlessly. Certain teenage girls seem to go for days without food or drink because their mouths are otherwise engaged. Others, who clearly do not know better, seem to think chat is an art-form.

So how much time would, could, or should a government spend monitoring this Babel? How worthwhile might the enterprise be? How much would the effort cost? Would the security of staggering quantities of data ever be guaranteed? Could such a project ever be brought to fruition? Oh, and a small detail: by what right?

We are, reportedly, about to find out. Not dissuaded by its serial failures to manage giant IT projects in everything from the NHS to air traffic control, the Home Office means to press on with the biggest communications database of them all. Forget the ID cards cock-up. Forget - the government wishes you would - an official inability to secure a few laptops and memory sticks, far less the nation's privacy. Forget that all previous promises as to controls, safeguards and misuse of data have been breached. Forget even that the plan, in a country on its uppers, could cost the equivalent of another couple of banks. They want it.

Don't forget two things, however. First, this "interception modernisation programme" is to be privatised. Which is to say that a commercial entity will be asked to "manage" - spy on - our most intimate personal information. For New Labour, the distinction between what might, just, be allowed by a citizenry to an elected government, and what might be allowed to a bunch of suits turning a quick buck, has been eradicated.

Secondly, remember something more significant. Not "it won't work", though that certainly amounts to a very good bet. Try this: why is it that no other government in the world, from a basic paranoid dictatorship to a terror-obsessed United States, is even contemplating this version of universal surveillance? Is the Home Office right, for once, while everyone else is wrong? Have they been sold a pup by software hustlers? Do they truly believe that knowledge of your emails to auntie in Australia is actual power? Or has the logic of technology begun to seem inexorable: we can do it, therefore we must?

Put this on file. Were I to be organising a plot against the bees in my bonnet, I wouldn't use a phone, not even a pay-as-you-go. I wouldn't touch texts, emails, or the net. I wouldn't go near any street with a CCTV camera, or risk those car number recognition gizmos. I wouldn't trust a keyboard exposed to key-logging, or to any of that other fancy stuff. I wouldn't even trust the dog. And for the efficient terrorist, the truly dangerous plotter, all this is elementary.

Phone companies and ISPs store the material investigators might require. Police can and do receive access, on application. It is, all of it, far more efficient, when real need arises, than anything achieved in the old days of bugs, letter intercepts and funny clicks on the land-line. Yet still Jacqui Smith, Home Secretary, intends to propose her "superdatabase" in a consultation paper to be published this month.

Everything and everybody. Every call, text, email, and web page briefly encountered. With extra-tough safeguards, obviously. And a snip, clearly, at a reputed £12 billion. And all - because we must always trust the people who certainly do not trust us - in freedom's name. Question my sanity if you will, but I'll be the one at the back of the queue when the psychiatric examination is announced.

They promise - they really do - to leave the content of your messages untouched. What, then, is the point? They promise that only very, very senior ministers will be allowed to control access to the system. Which part of that is plausible? And they say, while countries at greater risk than our own still value liberty more than information, that it is all essential.

Last week, Sir Ken Macdonald, a former director of public prosecutions, dismissed every reassurance. That, he in effect said, is what they would say, and it is "worthless". He spoke of a "hellhouse". He added a fundamental truth: "No government of any colour is to be trusted with such a roadmap to our souls."

In liberty's name we lose our liberties. Funny, that. The threat is always more important than the things we are supposed to be defending. This isn't new, but I would add something: you are liable, I think, to hear more about it in 2009.

Given the government's record, private data will no doubt be "mislaid": that's a worry. As Sir Ken argues, official promises in these matters can never be trusted: another worry. My actual grievance is more than theoretical, even at this early stage in the game: have free speech and privacy become actually worthless? Who abolishes these, and by what right?

It goes like this: those spied upon - spied upon universally, relentlessly, systematically - do not speak freely. Given Orwell and his Big Brother, the thought is hardly original. But the state in Nineteen Eighty-Four made no pretense of presumed consent. My information, my speech, my life, is mine, not a commodity to be disposed of by administrative fictions. Should Ms Smith and her department get their way, my identity, and 60 million other identities, will become state property.

This is not a small price to pay in the war on terror. It is, short of death, the highest price. And it will mean - don't you love a good black comedy? - that the terrorists have succeeded. We will have become the sort of repressive, oppressive paranoid country of their self-serving dreams.

But surely "only parliament will decide"? Won't our free-thinking, independently-minded MPs, liberty's guardians, see us right? So remember how they distinguished themselves over 90-day detention. And remember this: if the superdatabase is born, it will already be too late.

My suspicion, in any case, is that Ms Smith merely means to make official what is already existing practice. As Sir Ken Macdonald knows, that is how these things are done. But he, like the rest of us, doesn't know the half of it. In Britain, that's government's job, and now it wants the rest.

You can always read all of that twice, poor spook, if you think it might help.

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