David Aaronovitch: Don't rely on spies to protect us

'It will be the spooks' judgements that will inform the Home Secretary as he comes to decide who gets to be detained indefinitely'

Forgive my language, but of all the imagined or speculative incarnations of Osama bin Laden that have appeared in speech or print in the past two months, my favourite is bin Laden the dickhead. OBL the DH is the man who, by his apocalyptic provocation, ensured that the regime that nurtured him has been smashed and that the network he spent years constructing, has been hugely damaged. I like this image, and it strikes me as being as likely to be accurate as the hydra-headed monster OBL of the anti-war movement, or the Mephistophelean OBL of some popular magazines.

But even permitting oneself the consolation of OBL the DH doesn't tell you too much about the terrorist threat. For that we can only examine the record and chart the steady growth of suicide attacks, and piece together such other evidence as comes our way. We have the suburban Kabuli houses full of manuals, poisons and al-Qa'ida application forms (post now to avoid disappointment). We may guess that the shattering (if lucky) success of the 11 September massacres will inspire a generation of pitiless nihilists of all kinds to see if they cannot arrange something just as televisual.

And then there's what the intelligence services are telling us. Over the weekend, David Ignatius of The Washington Post wrote about an on-the-record briefing given to journalists by Jean-Jacques Pascal, head of the DST, the French counter-intelligence agency. M. Pascal said that, since 1998, his organisation had noted the return to Europe and America of hundreds of "neo-Afghans" – Arabs who had gone to be trained by al-Qa'ida and other, similar organisations. His agency had, he said, already prevented attacks in Strasbourg and uncovered a plot to blow up the American embassy in Paris. According to M. Pascal, out there right now are dozens of "artisanal" terror grouplets, just waiting their turn.

If that's true for France then it is most probably true for Britain too. At times like this (but when have there been times like this?) one longs for the austere protection of one's own spooks. For who else can save us from men who don't mind dying? And it will be the spooks' judgements that will inform the Home Secretary – should Parliament give him the powers when it votes tomorrow – as he comes to decide who gets to be detained indefinitely. They will tell him who the 16 to 20 (very precise, this) bad persons are, for whose benefit we will have derogated on Article 5 of the Convention on Human Rights, now incorporated into British law.

I can buy the necessity of doing this. Just. My nightmare, and one that I have shared with readers before, is what would happen to race relations in this country should some terrorist, acting in the name of Islam, decide to kill a whole load of citizens here. There is a mythology about British sang-froid and tolerance that I do not care to have tested. But the effectiveness of this measure depends precisely upon its limitation and its forensic use. And that's where my worries begin.

With, if you like, Stella Rimington, the retired director general of MI5 and her autobiography Open Secret, published a couple of months ago. Back in 1969, Stella, as a trainee, was practising her trade/craft on the Sussex District of the Communist Party of Great Britain (a district, if my memory as a former party member serves, full of ancient, inert Stalinists), while reading the works of that unpleasantly racist forerunner of Ian Fleming's, Dornford Yates.

Soon MI5 – like the country, according to Stella – was experiencing a "period of very considerable political upheaval" which necessitated MI5 keeping tabs on domestic subversives.

She lists the rise of CND, events at Greenham Common, the miners' strike and the growth of the militant tendency, and continues, "most of the subversive activity... which was going on at that time came from the communists, acting at least from the centre, on advice and support from the Soviet Embassy...".

We are talking here about the years from 1978, say, to 1985. And in this time, says Stella, Soviet and East European intelligence officers were "funding and directing national communist parties to try and gain influence in... groups like CND and the unions".

She further added, at the time of the book launch, that "Soviet officials encouraged Western communist parties, such as the Communist Party of Great Britain, to try to infiltrate CND at key strategic levels by getting their members elected as officers". So, of course, the activities of the Communist Party and Communist Party members had to be monitored.

I have a problem with this. Which is that it's garbage. No one on the left in the late 1970s and 1980s – as Brezhnev and then Andropov stared back at Reagan over a forest of newly deployed intermediate nuclear weapons – needed Igor from the embassy or Bert from the committee to tell them to join CND. Actually, the opposite was true. In several instances I remember comrades being gently advised not to take up office in CND, lest the Communist Party be seen to be too dominant. As often as not they would ignore such advice.

That was not surprising. Far from being an insurrectionary party, since the early 1950s the CPGB, through its manifesto the British Road to Socialism, had espoused parliamentary democracy. In 1968 it condemned the Soviet "intervention" in Czechoslovakia and by the time in 1979 that it condemned the "invasion" of Afghanistan, it was hardly on speaking terms with the Soviets. During the period of "upheaval", the CPGB had long been a left-social democratic and socially liberal party, more interested in gay rights than in workers' committees. And yet this was the party that Stella and MI5 spent so much time tailing, tapping and getting their under-garments in a twist about. It was a complete waste of their time and our money.

Had she, I wondered as I read her book, actually ever spoken to a senior communist? Has she even now? Following the mild establishment criticism of her decision to publish her memoirs she said she felt hurt.

Stella said: "I think I understand better what people outside feel when they're trying to deal with the state, or particularly with the secret state, and how – perhaps it's a bizarre exaggeration for me to say this – how 'got at' you can actually feel." Amen. And then she goes on to tell us how the service employed obsessive cranks like Peter Wright, and – when they got too mad – promoted them to positions such as special adviser to the director general.

And it is their descendants who will be telling Mr Blunkett which suspects to bang up without trial. On television at the weekend, the Home Secretary told Sir David Frost not to worry. "No one is going macho," said Mr B. "No one's trying to do this for the sake of promoting some sort of vitriolic or anti-human rights agenda." Good. I trust old Blunkett. But I can see from Stella's minor idiocies, and from her admission that it hurts to be the victim of the state's displeasure, that these powers need to be scrutinised properly.

The annual parliamentary renewal of the old Prevention of Terrorism Act became a whipped 12-monthly event – a bit like Christmas in prison. The renewal of the new derogation must not be allowed to go the same way. If it does, then we'll all have been dickheads.

David.Aaronovitch@btinternet.com