Comment: Punish them for spying on you

The Home Office does something to them. A Home Office chat will turn the most marvellous of libertarians into a curtain-twitcher. What do they do to them in those dark corridors? They walk in like Braveheart and leave like Sweeney.

It took them two years to wear the coalition down. Liberal Democrats have an outstanding track record on civil liberties, although their greatest champion on the issue, Chris Huhne, is currently off fighting a legal case. The Conservative leadership, after some dithering, also committed to privacy, although it was left to backbenchers like David Davis to do the heavy lifting. But finally, after two years, the Home Office is feeling confident again. It's convinced them to resurrect a 2009 proposal for expanding surveillance.

The difference between now and the New Labour years is that civil liberties campaigners are not on the back foot. Politically, the wind is blowing in their direction. Liberal Democrat MPs have been bruised by their betrayal over tuition fees and the public animosity it created. They are wary of any more broken promises, of haemorrhaging their remaining supporters. The Tories, sat next to their coalition allies on the green benches, have seen what happens when your old promises are compared to your current actions. Even Labour, the party with the least understanding of the appropriate limits to state power, is run by a leader who made a special pledge to civil liberties campaigners - even if his shadow home secretary is clearly an unreconstructed authoritarian.

All three parties are vulnerable to a concerted campaign to prevent any further expansion of the state's ability to snoop on your private life. And you couldn't get a more definitive, over-reaching attempt than this.

The Home Office is treating you like an idiot. First, it refuses to release details of the plans but sends out its supporters to bat for it. Without knowing precisely what is planned, its supporters loyally give media interviews promising to catch paedophiles and terrorists. This is the most despicable propaganda, intended to mislead you and use your best instincts against you.

We don't know precisely how the Home Office plans to accomplish its goals, but we know what the goals are. From that, we can deduce the rest. The government wants to be able to check third party communications. Not just your email or phone, which is between you and the provider, but your communications on services such as Skype or Facebook. The only technologically and legally feasible way of doing that is to install black boxes at the internet service providers, meaning everything you do online is documented – every click, every instant message, every search.

They claim they won't look at the content of your messages – you need a warrant to do that under existing law. But the system would allow them access to that content. The only thing stopping them is their deeply held ethical code, which is not something it's wise to rely on when dealing with anonymous state officials.

The proposals would make it almost impossible for technology companies to reject demands from authoritarian regimes overseas. What possible reason could they have, beyond base cultural relativism, for rejecting their demands while fulfilling those of the British government? And how contemptible for the British state to have reduced itself to the level of an authoritarian regime, without even a recent terrorist attack to excuse it.

Look at the price tag. As ever, the penny-pinching attitude of the government melts to nothing when faced with the demands of shady security officials. On the 2009 estimates, the project would cost £2 billion in the first ten years and £200 million each year after. This is because internet service providers have no business reason to collect the data the government wants, so the taxpayer has to step in. The price has almost certainly risen since then. Even if it hasn't, government IT projects rarely, if ever, come in at the estimated price. The deficit is that occasional ghost: appearing suddenly when you want disability benefits but nowhere to be seen when you want your freedoms.

The proposals fundamentally alter your relationship with the state, in the same way ID cards threatened to. Instead of them asking to see your data, they have it by default. The argument will no longer be about when it is OK to spy on someone. It will be about when someone is trustworthy enough not to be spied on. Even without content – a government promise you should treat with a bucket of salt – it could put together detailed descriptions of your life by your online activity, the Google searches you do and the emails you send - from dating sites to music choices. How long before behavioural data analysts start to make suggestions about personality types and crime? How long before we start to predict it?

The current behaviour of the security services has been exemplary. Several attacks have been foiled, no attacks have succeeded. If civil liberties campaigners cannot win the arguments now, free from press hysteria, under a supposedly sympathetic government, they never will.

The Home Office is making a power grab. It has laid low for two years, aware that the coalition is united by civil liberties. But now it is making its move, bending ministers' ears. This time, things are different. Liberal Democrats and Conservatives are acutely vulnerable to a vocal campaign in a way New Labour never was. Make sure they know you'll punish them.

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