That was one of the reasons. A more philosophical one was that domestic espionage undermined popular confidence in the authorities, making the exercise of authority more difficult. If they don’t trust us, why should we trust them? These restraints gradually dissolved during the 20th century, partly under the cover of the world wars, and in the fever of paranoia after the Russian revolution. That came to a head in the late 1960s and 1970s. The farcical plot against Harold Wilson, who was suspected of being a Soviet mole, happened at exactly the time as the Special Demonstration Squad (SDS) — motto “By Any Means Necessary” — was secretly set up. In retrospect, the year 1968 can be seen to mark the beginning of Britain’s Great Reaction, which has gone on (and on) since then. In Britain it is the right wing that has generally been most willing to use underhand methods against its perceived enemies, and to defend these methods openly: “If you have done nothing wrong you have nothing to fear.” It is also the right who tend to cry “conspiracy theorist” at anyone who suspects this kind of thing. In the view of Evans and Lewis, the conspiracy theorists have been “not nearly paranoid enough.”
The question remains whether these methods can be in any way justified by their results. The circumstances of today are different from those of the 19th century. It is arguable that there are more subversive dangers now: though there were plenty of things that the Victorians could have painted as subversive if they had been so inclined. Perhaps the switch from being the most proudly “spyless” of nations to possibly the most spied on — surveillance cameras, GCHQ, Prism, industrial “blacklists” and the like — had to come. But it is difficult to see the SDS fitting into this rationale. IRA and Islamist terrorists are one thing. (Bankers might have been another, if only we had realized where the real danger lay.) But tree-huggers, veggies, anti-imperialists and animal rights campaigners — the SDS’s main targets? Come on!
With all this going on, it may not be surprising that popular trust in government is breaking down. It is what the Victorians would have expected. We’re no longer so surprised by revelations such as this, which is sad. But the real change will have come if we are no longer outraged by them — then we really will have changed as a nation. With luck, the grotesqueries revealed in this powerful book will fire some of the old free and radical British spirit again. But don’t wait up.