SHOCKED, or not shocked? The chasm widens. The New York Times this week carried a story from a whistleblower close to Washington's foreign intelligence surveillance court, known as the Fisa court — a secret body set up in 1978 to monitor federal phone taps. It now gives legal cover to intelligence trawling of millions of individuals, at home and abroad.

The recent revelations by another whistleblower, Edward Snowden, accused the court of breaking the fourth amendment to the US constitution. This entitles Americans “to be secure in their persons, houses, papers and effects, against unreasonable searches and seizures”. The operative word, as so often, is unreasonable.

The new leak alleges that more than a dozen new “rulings” have been passed by Fisa, declaring categories of data-scooping that were within the “special needs” of security, and thus no different from breath-testing or body-searching at airports. NSA operations such as Prism, Tempora and Boundless Informant — many in collusion with Britain's Government Communications Headquarters (GCHQ, the UK's signal intelligence agency) — used covert access to Google, Apple and Facebook to go where they pleased. They could cite not just terrorism but espionage, matters of interest to a foreign power, cyber-attacks and “weapons of mass destruction”.

These judgments, all in secret, confirmed the gist of Snowden's evidence — and validated his motive. The reason why a previously loyal ex-soldier broke cover was not to aid an enemy. It was to inform a friend, his own country. He was simply outraged by the lies told to Congress by his bosses about National Security Agency (NSA) operations. As Harvard's Stephen Walt has said, Snowden was performing a public service in drawing attention to a “poorly supervised and probably unconstitutional” activity.

The New York Times pointed out that the Fisa court had become a “parallel supreme court”. It catered to a mirror universe beyond the reach of Congress or normal courts, servicing a new and burgeoning realm of government and private securocrats. When asked about this world, NSA bosses merely said they could not “jeopardise American security”. Snowden's revelations are in a different league from WikiLeaks. They are not embarrassing diplomatic gossip, but a window on method, on a legal no man's land created in near panic by America and Britain after 9/11. With unconstrained budgets at their disposal and infinite scope to terrify paranoid politicians into doing their bidding, agencies intruded into every corner of the nation's and its citizens’ life. They filled their gaping larders with data to be harvested by their algorithm profiles against a rainy day. Nobody controlled them.

Some are unworried by this. Speaking on the BBC's Moral Maze radio programme on Sunday (July 7), Baroness Neville-Jones, the former co-ordinator of British intelligence, told listeners that the British authorities “behave in a perfectly law-abiding fashion” and have never done “something wilfully wrong or illegal in the public interest”. Besides there were “safeguards” in place, secret ones.

Britain's foreign secretary, William Hague, agreed. He denied flatly what Snowden had revealed. Speaking on television, he deployed the policeman's apologia down the ages: “Law-abiding citizens have nothing to fear, absolutely nothing.”

To my knowledge, no US source has denied Snowden. The rulings passed by the Fisa court suggest he was spot on. Even President Obama welcomed a debate on the revelations, and a possible amendment to the patriot acts. America is able to be grown up on the subject.

I read Snowden's latest material alongside John le Carre's new novel, A Delicate Truth, almost a commentary on the Snowden saga. He leaves the old certainties of the cold war behind and enters former British prime minister Tony Blair's moral swamp. The hero is a Snowden figure, Toby Bell: “that most feared creature in our contemporary world: a solitary decider”.

Bell is no longer fighting an ideological foe. His enemy is now his own side, represented by a Blair crony minister and henchmen. The establishment is corrupted by money, in cahoots with the mercenaries of intelligence and extraordinary rendition. Politicians and officials are alternately venal and paranoid.

When I heard Hague say the innocent had nothing to fear, I distinctly heard Le Carre give a hollow laugh.

When a disreputable newspaper upsets the publicity image of a Hollywood celebrity, the services of the police and the bench of judges are at his disposal. The press is universally castigated and brought to book. When agents of the state do far worse, the system gathers round to protect its own.

Any fool can see that electronic data scooped into a “top secret” cloud are virtually free to air. That is why counsel in British trials are advised not to use email lest it be accessed by police and prosecutors. It is why a blameless Muslim lawyer found himself hauled off a Chicago plane and told by the FBI to spy for them or never get on a plane again. It is why no one's medical records would be safe from insurance companies were the data they contained to go online.

In an interview published on Monday, Snowden said he did not want to live in a world where “everything that I say, everything I do, everyone I talk to, every expression of creativity or love or friendship is recorded”, and then stored and judged by the state for possible use. Once on the list there is no redress.

US civil libertarians are seeking to confront the assault on the fourth amendment, possibly before the proper supreme court. Britain has no such recourse. It has only a foreign secretary assuring it that Snowden is talking nonsense. Privacy International, the UK-based charity that defends and promotes the right to privacy across the world, is seeking a legal challenge to the data-scooping of NSA and GCHQ. The British government has refused to let such a case come before a public court. As for expecting the British media to come to liberty's defence, forget it. The GCHQ aspect of the Snowden story followed a reminder from the government's D-notice committee, (which issues official requests to news editors not to publish or broadcast items on specified subjects for reasons of national security) and, coincidentally or not, appeared only in the London-based Guardian, which broke the NSA story. The justification for this system - even from journalists - is that without it “something worse” would happen. This was a boat already rocked by the American president and every government in Europe.

I feel sorry for novelists like Le Carre. Fiction can never capture the full horror of truth.

By arrangement with the Guardian