Compare a democracy to a dictatorship and world-weary chuckles follow. The last thing a citizen can do in true tyrannies is call them tyrannies. He or she has to pretend that the glorious socialist motherland or virtuous Islamic republic is not only as free as democracies but has a level of freedom that those who rely on universal suffrage and human rights cannot attain. If you are free to call your country a tyranny, then it is almost certainly is not.

In the United States, the politically sophisticated are enjoying themselves immensely as they tear into leftish claims that America is now George Orwell’s all-seeing totalitarian state. To their way of thinking Edward Snowden’s revelations on how the American government is engaged in mass surveillance are less interesting than the hysterical reaction his whistle blowing has provoked.

‘The rule here is simple,’ said Michael C. Moynihan, one of America’s best right-wing journalists, as he dismissed the notion that the United States was Oceania. ‘If you are invoking Nineteen Eighty-Four in a country in which Nineteen Eighty-Four is available for purchase and can be freely deployed as a rhetorical device, you likely don’t understand the point of Nineteen Eighty-Four.’

I can imagine Dave Morris’ outraged reaction to today’s news that he had been the victim of a police agent provocateur producing another bout of condescension. Morris and his fellow green activist Helen Steel were on the receiving end of a libel action from McDonald’s that consumed three years of their lives. The case was notorious – ‘it has achieved what many lawyers thought impossible: to lower further the reputation of our law in the minds of all right thinking people,’ as a leading lawyer said at the time. McDonald’s spent millions of pounds hounding Morris and Steel for producing a rough little leaflet, which denounced the corporation’s environmental record. In a forthcoming book Paul Lewis and Rob Evans of the Guardian reveal that the leaflet was the work of Bob Lambert, an undercover police officer, who posed as an extreme animal rights activist so he could spy on radical greens.

‘We now know that other shadowy forces were also trying to undermine our efforts in the most disgusting, but ultimately futile ways,’ Morris said when he heard what the authorities had done. ‘All over the world police and secret agents infiltrate opposition movements in order to protect the rich and powerful but as we have seen in so many countries recently people power and the pursuit of truth and justice is unstoppable, even faced with the most repressive and unacceptable Stasi-like tactics.’

Stasi-like tactics? To compare Britain to a Stalinist state is like saying America is living in an Orwellian nightmare. It is hyperbolic, false and absurd.

But think twice before joining the scoffers. Complacent westerners fail to understand that freedoms are guarded because their defenders are prepared to go wild. They do not seem to know that each generation has to struggle to maintain the freedoms it has inherited and to adapt them to meet alarming changes in the behaviour of the powerful. Hyperbole is inevitable and not always ridiculous. Unless you can imagine where ominous policies might lead, you are unlikely to find the motivation to give up the pleasures of your comfortable life and engage in the time-consuming and often tedious business of campaigning against them. The claim that ‘Western countries are becoming dictatorships’ is false. But it will only stay false if enough activists, politicians and judges are prepared to fight to stop dictatorial tendencies growing.

Meanwhile, although it remains absurd to say that Britain is a Stasi state, it is far from absurd to think that this tactic used by the Metropolitan police or that demand for data from the American National Security Agency echoes the behaviour of a tyranny’s secret police force. Just because democracies are not dictatorships does not mean that they cannot act like dictatorships if an apathetic or frightened citizenry allows them too much leeway.

I suspect that Snowden’s revelations have caused such interest because he told us something we half knew but did not want to think about. Computer technologies have made mass surveillance incredibly easy. In the 20th century, governments would have needed vast spy networks – a genuine Stasi, if you like – to track everyone’s movements or listen in to every phone call. Now the British government can propose ordering telecoms companies to collect information on billions of communications – just like that. No one says that blanket surveillance is impossible or too expensive to contemplate or beyond the resources of the state. We know that it can be done all too effortlessly.

The story of Bob Lambert is as sinister. He was a member of the Metropolitan Police’s Special Demonstration Squad. Its officers not only spied on radical greens – a legitimate activity, I suppose, because animal rights activists can turn violent – but acted as agents provocateurs, who incited crimes, which otherwise would not have been committed. Using a false name, Lambert seduced four women, and fathered a child with one of his lovers. When his undercover assignment finished in the 1980s, he disappeared from their lives. She had no idea where he had gone or who he was until journalists exposed his secret past in 2011. What is that woman and her child meant to think of a British state that used taxpayers’ money to employ a secret policeman, who treated them so? That it is benign and decent, and anyone who suggests otherwise is a paranoid hysteric?

The Metropolitan Police disbanded his unit. But Lambert’s supposed expertise on extremism had a malign influence on public policy. He became foremost exponent of the idea that Britain should combat radical Islam by embracing theocratic groups such as the Muslim Brotherhood and Jamaat-i-Islami, which were ultra-reactionary but non-violent. Liberal Muslims and ex-Muslims, who just wanted to enjoy liberal freedoms everyone else took for granted, found that the last Labour government, much of the public sector and a large section of the wider British left were saying that men who wanted to crush their aspirations were the sole authentic representatives of their “community”. Lambert’s contemptuous treatment of women in the green movement was matched by his willingness to ally with misogynists on the religious right.

There is a danger of using alarmist language when writing about the behaviour of the secret state. But there is an equal danger of not being alarmed enough. Freedoms survive because people struggle for them. You can mock their willingness to descend into hyperbole, but without it they cannot emphasise dangers at a time when new technologies are giving dangerous new means of control to the state. The price of liberty is not just eternal vigilance but perpetual exaggeration.

Tags: Freedom of speech, George Orwell, Islamism, Police, United States