This process could last for a long time during which the so-far suppressed anger of the American people could break out into a rage for revenge. The anguish of those who already know they have lost family or friends will be surpassed by those waiting for news of the missing, not knowing whether they are in hospital, lying injured beneath the debris, or already dead. The only comparison that comes to mind is with a catastrophic earthquake - but with the bitter realisation that this is a manmade rather than a natural disaster. There is little point in dwelling on this human suffering. It is there for all to see and our sympathies, however heartfelt, cannot really help. It is more important, I think, to direct our concern to an understanding of what happened, why it happened and how similar abominations might be avoided, or at least limited, in the future.
It is first necessary to accept that there exist in various places in the world men whose hatred of the United States as a symbol of the oppressive West is so great that no sacrifice is too great for them to make in order to cut off the head of the American snake. (It may be worth pointing out the fallacy of the assumption that all suicide bombers are impressionable young teenagers who have been brain-washed into sacrifice). Tuesday's suicide pilots and their collaborators must have been mature men able to carry through their assignment confidently, to direct the planes very expertly on to their targets - and at no point in months of preparation to have wavered in their belief in the rightness of their cause. Perhaps twelve such men died in the four highjacked planes on Tuesday; there will be at least twelve times that number ready and willing to follow their example.
Why should such hatred exist? There are probably many causes, as is inevitable when a nation as strong and assertive as the United States involves itself - often altruistically and beneficially in all four quarters of the world. But the single greatest cause is America's undiscriminating identification with Israel in the Middle East. This has provided a focus for Islamic anger because hundreds of thousands of Arabs have lost their homes and their land, tens of thousands have been killed, and today Palestinians are obliged to live in conditions which most closely resemble the notorious homelands used by the South African apartheid governments to keep their blacks under control. It is estimated that there are likely to be 20'000 deaths in the Twin Towers. Almost the same number of civilians were killed in Israel's 1982 invasion of Lebanon. Such a crude comparison may seem obscene - but it will seem entirely relevant to the kind of person who carried out last Tuesday's atrocities, and to many of those on whose behalf they believe they acted.
Is there any possibility that this selfperpetuating hatred can be ameliorated? The answer to this question hangs, initially, on President Bush's reaction to the crisis he faces. He has already promised to track down those responsible and he will be under enormous pressure from the American public to name the guilty quickly. He has also said that countries which harbour terrorists, even if they do not actively support them, will be considered legitimate targets for retribution. But if Mr Bush does not want to make a bad situation worse he should proceed with great caution.
The difficulty in assembling castiron evidence in cases of this kind was amply proved by the Lockerbie trial. The dangers of precipitate action were shown by his predecessor's action in lobbing missiles at a misidentified target in the Sudan shortly after the US embassy bombings in Africa in 1998. If President Bush does rush to judgement without adequate evidence he will risk alienating the moderate Arab leaders whose support is so important to a longterm solution of this intractable problem. He will also try further the patience of his instinctive allies in Europe and elsewhere who have already felt distanced by several of his arbitrary actions in international affairs. On this issue, however, if he resists public pressure for quick results and acts only on sound evidence, Mr Bush has the opportunity of building a solid coalition of likeminded nations of many different political persuasions which are united in their wish to see terrorism brought under control.
But even this would be an insufficient guarantee of future freedom from terrorism unless the president also gives serious consideration to a recasting of America's Middle East policies.