Howard Jacobson: When you live with the threat of destruction, there's no alternative to throwing a party

This week has been uncannily reminiscent of last year. The bombs exploded into just this summer idyll

"Thoughts A Year On" was the poncy title I originally envisaged for this column, so it's a good job the paper employs somebody to come up with something better. It will of necessity have been filed, whatever it's called, before the anniversary of last year's terrorist atrocity has been negotiated. I am therefore writing in ignorance of whether any crazed attempt to mark that anniversary with further blood has been successful. Perhaps the heightened vigilance will have deterred the celebrants. Perhaps they will have decided to consecrate another date to murder. But that it will be tomorrow if it was not yesterday, or the day after the day after tomorrow, I do not doubt. For nothing has changed in the last year, and maybe nothing can change. The fires of an irrational rage still burn, and we lack the will or know-how to put them out. Indeed there are some among us who think we deserve to go up in flames. To say we had and have it coming is not incitement exactly, but the self-hate of our society without doubt contributes to a climate in which a terrorist feels justified in seeing himself as a soldier in a worthy cause.

Whether this means we are in one of those declines which a future Gibbon will describe as the "inevitable effect of immoderate greatness", only generations yet unborn will know. Unless we implode sooner than that. Either way, Gibbon's description of Rome submitting to a simple physical law - its "stupendous fabric yielding to the gravity of its own weight" - works just as well for us.

This week has been uncannily reminiscent of the same week last year. The weather glorious, sport the only topic of conversation, the whole of London given over to carnival. Spontaneous carnival, most of it, which is the best sort. People simply loving where they are and wanting to be outside in sight of one another, seeking the infection and corroboration of pleasure. The bombs exploded into just this summer idyll last time. Pure fancy, of course, to suppose the contrast made the carnage crueller. Nothing makes it crueller. Blow up people you do not know because you feel aggrieved - regardless of the justice of your grievance - and your crime mocks any concept of worse or worst. There is no worse.

We don't do egregious crime any more, I know. Judges refuse to countenance the idea that any act puts a man beyond humanity, and society as a whole is terrified of condemning with that stringency we associate with the mob. Today, judgement is confined to the popular press. The rest of us extenuate and extenuate until we have no vocabulary for outrage left. Thereby leaving the field open to those whose violence looks like rectitude, if for no other reason than that they can be said to believe in something. By such logic do murderers persuade us they are moralists.

Meanwhile we party. I am not complaining. I love the partying. Perhaps it is some weakness in my nature, but I have never been convinced by the argument that we shouldn't party when there are more serious things afoot. It is precisely when there are serious things afoot that we should party hardest.

We partied more optimistically last year. London had been awarded the Olympics, our cricketers had an air of victory about them, and the World Cup was still a year away. Now we are back losing at everything. By early evening on Saturday last the footballing revels were over. Troops of young men with flags draped like shrouds around their bodies straggled through the streets like a defeated army. I had watched the match in a bar in the city. No trouble. After the penalties, one man punched a table, gave a V-sign to the Gods, then let himself be escorted away. Otherwise just mass deflation, the bar emptied in seconds, as though we'd never been. Round and round in my head went the lines of that Al Jolson song about the Spanish bull fighter. "If I catch Alfonso Spagoni the toreador, ah ha ha. With one mighty swipe I will dislocate his balley jaw, ah ha ha." "The Spaniard That Blighted my Life", it's called. Spaniard, Portuguese- same difference. They all blight your life.

Back in my neck of the woods a gay march was also breaking up. Again peaceably, if you discount the two lesbians tearing out each other's throats, and the disoriented football fan who instead of shedding tears for Rooney decided to punch a midnight cowboy in his solar plexus. Homophobia? Hard to tell what it was. There was the cowboy in white thigh-high boots, shiny posing pouch and a Stetson, pausing to tongue his boyfriend in the doorway of a hardware shop on Brewer Street, and there was the football fan with his fists handy and nothing else to do with them. And thus the two collided. I am not saying it was not shocking. If anything, the motivelessness of the act, its faut de mieux randomness at the end of a wasted day, made it more shocking than had it been a calculated assault. It reminded one what undirected violence sloshes around inside the human animal. "He shall die! He shall die. He shall die tiddly-I-ti-ti-ti-ti-ti-ti! For I'll raise a bunion on his Spanish onion if I catch him bending tonight."

How else are you meant to relieve your feelings? There was an end of the world atmosphere about that Saturday, with its lost legions of England supporters, blubbering into their fists, and Soho filled to overflowing with sexual revellers, drinking, eating, kissing and carousing in the heat. The idea we have of Rome degenerating into an orgy of sex and violence is not quite Gibbon, but even on quieter evenings, as you dodge the limo-loads of vomiting brides-to-be, and queue alongside toddlers to buy champagne in Oddbins, it is hard to avoid the conclusion that at some deep level of intuition we know that what awaited Rome awaits us.

On Tuesday, Soho became a sort of Rome, with hundreds if not thousands of Italians gathered outside Bar Italia to watch Italy put out Germany. Good to see someone pleased about their football team. And even better to be reminded how generously London accommodates passions not our own. No, it didn't seem as though Armageddon was round the corner as they waved their flags and danced. But then they had just won. By Sunday night they too might have turned into a dispirited army.

But that's the point of parties. We carouse as though there's no tomorrow, either because we fear tomorrow, or because there is no tomorrow.