New York's police commissioner called it "a war zone" and many others followed him in that description. The truth in that sad banality is not simply that the casualties are as grave as on many a battlefield, or that the organization of these attacks was, alas, like that of a highly efficient military operation. It is also that in a number of places in the world, including the United States itself, as Oklahoma City showed, there are groups who consider themselves at war with America.

It is true that their number is small. The list of possible culprits is short. The world is not full of people who want to kill Americans. But there is a potentially deadly combination of literally suicidal audacity, recruitment from among alienated youth, modern means of destruction, and the inattention of governments who are either incompetent at controlling terrorist groups or who look the other way for political reasons. We can add to that the cover which diasporas in both North America and Europe can provide for terrorists, largely by allowing them to remain anonymous and untraceable. This is the combination that has almost certainly brought this tragedy upon us.

We have seen it before on a lesser scale. But a terrorist success of this size is something new. It could be emulated in other continents. It could be emulated with chemical or biological weapons - the Tokyo subway attack was a warning of that possibility - or with nuclear weapons. The irony is that America's sense that it is vulnerable to rogue attack, which its allies sometimes decry, has been shown to be correct. But, at the same time the instruments which American governments, and especially this one, have been preparing to remedy that vulnerability are shown to be either inadequate or irrelevant.

Extraordinary long-range aerial military capacity, the ability to strike at will and perhaps even from space at any point on the globe, does not provide sufficient means to destroy terrorist groups. These left Osama bin Laden and his men, the most likely perpetrators of yesterday's atrocities, untouched after the bombing of the East African embassies. Missile defense, of course, would be irrelevant to such attacks, which remain the most likely way, as so many critics have said, of conveying nuclear weapons on to American soil.

America's best defense against terrorism originating from abroad remains the existence of governments and societies more or less satisfied with American even-handedness on issues which are important to them. Plainly, this is furthest from the case in the Muslim world. That is largely because of American policy on the conflict between the Israelis and the Palestinians, but also because there are some Arabs and other Muslims who also regard American and Western ascendancy as affronts in themselves.

Contrary to stereotype, however, most Arab and Muslim, and especially Palestinian, radical groups set limits for both practical and moral reasons on the violence they consider permissible. They may not be limits which we, or Israelis, like, but they are limits all the same, and they are well short of planning anything like yesterday's attacks. Osama bin Laden's limits are another matter, which is why he is the prime suspect here.

The head of the Democratic Front for the Liberation of Palestine, in denying that his organization had anything to do with the attacks, nevertheless went on to say yesterday that the discontent and anger which American policy was creating meant that its approach to the Middle East should be reviewed. His point is obvious. Anger is an asset which entrepreneurs of violence like Bin Laden can use. Would a settlement of the Israeli-Palestinian conflict and the establishment of an adequate Palestinian state end all Muslim terrorist violence? Perhaps not, but it would go a long way toward doing so. This not to argue that Washington's Middle Eastern policy should suddenly change because of these attacks. That would indeed be to argue in favor of blackmail.

But that policy is part of a broader problem. As analysts like Paul Rogers of Bradford University have argued, there is a clear danger that the rich world as a whole, and not only the US, will pursue a policy of "keeping the lid on" much of the rest of the world's discontents. Fundamental problems of injustice and inequality get palliatives and an increasingly sophisticated military is supposedly in reserve, but actually not that competent, to deal with the resulting troubles. These are usually outbreaks of violence within or between poorer states, and they can also lead to breakdowns of state authority, or its assumption by groups completely unprepared to exercise power - and to havens for extremists.

That, after all, is the story of Afghanistan. The US and Russia together helped turn Afghanistan into the backward and dangerous state that it has become. The US and Pakistan, with some British and other help, notoriously encouraged, because it was useful to them at the time, the rise of fundamentalist groups and the pan-Muslim recruitment of fighters. Out of this came the Taliban and Osama bin Laden.

Americans understandably want pursuit and punishment. What nation would not in these circumstances? This was above all a stupendous crime. But it does not minimize that crime or take way from the need to identify and punish to say that this pursuit should be international, and that if the crime was planned in Muslim lands, the anticipation of Muslim governments is essential. Nor does it minimize the crime to say that western policy may have played a part in creating the anger which led to it.

Finally it is proper to say that, while there is a global problem of inattention to injustice which is piling up trouble for the future, we are not yet facing an anarchic array of dangerous states and extreme movements. Terrorism is in fact more confined and has fewer havens than in the past. This outrage should not be a signal for the west to pull up the drawbridge but rather for a renewed international effort to deal with the fundamental problems that will blow up in all our faces if we let solutions drift away.

© Guardian Newspapers Limited 2001

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