Howard Jacobson: So it's not Iraq or Afghanistan that drives terrorists - it's drunk women in nightclubs

So now we know where the destruction of Western civilisation is being plotted: not in the madrassas of Karachi and Lahore, not in the Taliban training camps of Helmand province, not even in the eschatological fantasies of Mahmoud Ahmadinejad, but in Crawley, West Sussex. I am not of course suggesting that we rule Karachi and Tehran out of the topography of terror altogether, only that we adjust the range of our apprehension and learn to grow afraid of the loathing for the way we live that's being brewed just around the corner, in the suburbs, in the green belts, in the new towns of our fair and pleasant land. Crawley, West Sussex - never did sound fun, but never did sound dangerous either. But there you are, nowhere's safe, now we all know how to make explosives out of aftershave, from the menace which is certainty.

Call it Islamic certainty, but what emerged in the course of the fertiliser bomb trial was such a hotchpotch of prejudice, ignorance, sexual immaturity, woman-hating and theology, that the only one murderous component we can identify with confidence is the absolute conviction of right. Most of us have horrible attitudes and wouldn't mind putting a figurative bomb under something or someone or other; what stops us is that we think differently the next day. If we want to get to the bottom of why some young men don't feel differently the next day we need to understand why one brain freezes and another doesn't. Disaffection is not an explanation; it is a consequence. Blame religion if you like, but a half-baked university education can have exactly the same effect. It isn't straightforward charting the progress of fanaticism.

But the trial has thrown up matter which should embarrass more people than it can console. Good that we got the hateful little bastards, but lives might have been saved had we got them earlier. Much has been made of this, calls for a public inquiry into our policing and our security services, etc. But I wonder how many of those calling for this inquiry were busy telling us not all that long ago that there was no terrorism for our security services to police. An invention of our respective governments - Blair's and Bush's - the lot of it. An inveigling us into fear for the purpose of controlling us.

In America the voice of the hour was Michael Moore's - "There is no terrorist threat, somebody needs to just say there is." Over here a BBC2 series, The Power of Nightmares: The Rise of the Politics of Fear, spoke of the "dark illusion that has spread unquestioned through governments around the world", and in order to show that judges were not so easily made fools to an illusion Lord Woolf warned us we had more to fear from violations of the Human Rights Act than from terrorists.

So is that a "sorry" I hear amid the accusations that we have not been sufficiently vigilant? A sorry from those who thought vigilance was uncalled for and sinister?

Among the reasons to mistrust the rhetoric of human rights - not to be confused with our inalienable entitlement to freedom - is its politicisation. We most volubly declare the inviolability of the Human Rights Act where we deplore the government in power. Here is the danger of an incompetent and ignominious administration: it makes us incompetent and ignominious in our detestation of it, believing that whatever proceeds from it must be erroneous and whatever discomfits it worth praising. Our enemy's enemy must be our friend. So we jeered when a Labour Home Secretary ordered tanks to patrol the perimeters of Heathrow, and we allowed partisans of the ideology of terror to win the day when they complained of police in protective clothing charging for no good reason through their neighbourhoods of peace. Terror? What terror? Bombs in Crawley, West Sussex? Who would make a bomb in Crawley, West Sussex?

Thus does hating Blair turn us into self-harmers. We would rather be wrong about what is necessary for our basic safety than wrong about him. Shame on us!

And when we weren't accusing Blair of inventing terror for his own ends we were accusing him of fostering it - an extraordinary act of double-think in which we clamoured for a person to be charged with a crime which in another part of our minds we didn't believe had been committed. The terror whose existence we denied was the consequence of our invasion of Afghanistan and Iraq, the consequence of our neglect of the Palestinians, the consequence of a stream of attitudes and policies which it was impossible to construe as anything but anti-Muslim. And what was our evidence for this? Why, the terrorists who were not terrorists told us so. And for what reason do you do what you do, we asked - a question which any psychologist will tell you cannot possibly elicit the truth. And back came the answer: Iraq. Investigation closed. As though a person capable of planting a bomb cannot be capable of telling a lie. As though an ideologue of violence will not have worked out a self-justifying narrative of his actions.

So it is good if in other ways alarming news that the Crawley bombers were animated as much by disgust for what they saw in their own backyards as by anything we were doing in Baghdad. The words of Jawad Akbar in support of targeting the London nightclub Ministry of Sound - not the Ministry of Defence, note, not the Ministry of Tony's Lies - have rightly become famous. "No one can turn round and say 'oh they were innocent', those slags dancing around."

More than one commentator has noticed a certain home-grown quality in Jawad Akbar's language, something that has more in common with disgusted of Tunbridge Wells, or even amusingly appalled of Notting Hill, than Osama bin Laden. We should take the point. There aren't many of us for whom the sight of pissed-up brides-to-be spilling out of stretch limos in skirts up around their tushes is an occasion for national pride.

Disdain is not a fertiliser bomb, but it is still a good idea to remember how much we once liked getting pissed ourselves, whether in, or in the company of somebody in, a skirt up around the tush. There is nothing like recalling we have two attitudes to everything to stop us drifting into terrorism.

But a closed mind has its allure. And disgust can feel like power. That is why we should never stop being afraid. Just because a government we don't like tells us life is dangerous doesn't mean that life is safe.

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