In fighting this war with Afghanistan, the American and British governments seem—almost uniquely in recent years—to be acting wisely. Whether appearance is the same as reality, and, if it is, how long the wisdom will last, are matters beyond my ability to say. What I can do, though, is to give a dispassionate analysis of the war—of its causes and, assuming a basic rationality among its main projectors, its likely consequences.

The immediate cause of the war is obvious. It is last month's hijack bombings in America. The cause of these seems equally obvious. They were almost certainly not random acts of terror, or the beginning of some Islamic attempt at world conquest. More likely, they were an exactly measured demand for the Americans to change their policy in the Middle East. In one of his statements, Osama bin Laden summarised this policy under three heads. The Americans have stationed forces around the holy places of Islam. They have used these to fight a war against Iraq, and then to continue a blockade of the country in which many thousands of civilians have died from malnutrition and lack of medical care. They have given financial, military and diplomatic support to the state of Israel.

It is irrelevant to argue whether these policies are morally right or wrong. Millions of words have been written on either side, but they take us nowhere in this present analysis. There are only three considerations that are important. First, the policies are not required on any reasonable consideration of the American national interest. Second, they give huge offence throughout the entire Islamic world—Mr bin Laden is not merely stating what he thinks, but is acting as a general spokesman. Third, the means have been found to inflict catastrophic damage in response to the policies. Modern civilisation is wide open to terrorist violence. No western country needs to fear a military attack. But our large cities and extended division of labour provide almost unlimited opportunities for terrorism—especially if the terrorists are not themselves afraid to die in their attacks.

Given these facts, there is only one rational course of action for the Americans.

First, they need to pull back from the Middle East. They need to evacuate the Arabian peninsula, and call off the sanctions against Iraq. And they need to pressure the Israelis into offering a better compromise peace to their Arab subjects and neighbours than has so far been offered. Whether the Israelis have behaved as justly as they claim or as unjustly as is claimed against them is again irrelevant. All that is relevant is that American support for Israel of the kind given before last 11th September is no longer sustainable. Bearing in mind the facts of demographic change, Israel was already becoming unviable as a Jewish state within its present de facto borders. It now has less time than was expected, and many fewer options, to adjust to this fact. 

Second, the Americans must inflict a limited though memorable punishment for the bombings. Anyone who claims that these were themselves a just punishment, and so do not give excuse for an armed response, is missing the point. Regardless of any supposed justification, it is not convenient to let this kind of attack on a Western city pass without an armed response. That would show weakness, and leave us all open to further attacks—either from the same people or from others. As said, the punishment needs to be limited, so that it does not lead to an escalation of violence. But it needs to be overwhelmingly powerful, and should leave no one in doubt of what modern weaponry can achieve.

To their credit—and I am writing on the second day of the bombing offensive—this seems to be the policy of the American and British governments. Both Mr Bush and the British Foreign Secretary have indicated some willingness to consider a Palestinian state. However admirable these qualities might be in other circumstances, it is unfortunate for the Israelis that they now have a Prime Minister with all the vision and intellectual subtlety of a Prussian junker. But it is useful for the Americans in terms of public relations. We should also now look for some change of policy towards Iraq.

As for the war against Afghanistan, this seems to be limited, and does have reasonable justification. That Mr bin Laden really was behind the American bombings has not yet been fully demonstrated. But it is easy to believe that he was somehow involved; and the Afghan Government is refusing to hand him over to any credibly impartial court of investigation. Therefore, it is necessary to send in armed forces to arrest him and destroy the heart of whatever network he has constructed. We can hope that, once he has been captured or killed or otherwise removed from the country, the Americans and British will declare a victory and withdraw. This probably means that the present Taleban government will be overthrown and replaced by the Northern Alliance. It is unimportant—though regrettable—that these people may be much the same wild men with beards as the Taleban. It is equally unimportant and regrettable that any money they are given to rebuild the country will probably find its way into foreign bank accounts and the profits of various American and British armaments companies. All that matters to us is that those who are arguably guilty of the bombings should be punished.

Assuming continued rationality among the war's projectors, two further consequences may be expected.

First, we can hope that the Russians will be fully accepted into the concert of nations. Western policy towards Russia has been unwise for at least the past ten years. The country's established ideology is no longer Communism, but Russian Orthodox nationalism. This is incapable of export to the West, and does not require any hostility to the West. Therefore, it should have been more completely accepted that Russia has an interest in controlling its immediate neighbours. It was foolish to incorporate some of these neighbours into NATO, and foolish to offend it by attacking Serbia. The price of Russian support in this present war may be to start regarding it as the great power that it is and will remain.

Second, it is probable that the British debate on the European Union has now been settled at the top. Since the Americans are—at present—acting in the interest of all civilised countries in bombing Afghanistan, it is appropriate for other powers to support them. That Britain is the only power lending military support, while France and Germany offer only moral support, will not be overlooked in Washington. The hijack bombings destroyed the notion of American world supremacy. In future, the Americans will need to confine themselves to their own sphere of influence, and will need reliable allies to defend this. Britain is their only reliable ally. They pushed us into the European Union with the idea that we would keep the French and Germans securely in the American orbit. It is now clear that deeper integration into Europe will only detach us from that orbit. They pushed us in, and they may now pull us out. Mr Blair's mention of the Euro in his speech to last week's Labour Party Conference can be read as an act of politeness to the Europeans, but not as any statement of intent.

Looked at from the point of British or English survival as a nation state, a close American alliance is not in itself desirable. But it is probably better to have an overlord that speaks our language and shares our own traditions, than to be absorbed into an empire based on the Roman law.

Of course, I may be wrong in my assumption of rationality. It may be that I have misread the present situation. For example, I take Mr Blair's talk last week of a better world order as a moralistic gloss to a coldly realistic policy. Perhaps he sees the Afghan war instead as a necessary precursor to his better world order. This being so, we can expect yet another war without rational aims, and therefore an unpredictable escalation. To know which is the case, we must wait and see.

A further problem is that wars hardly ever go as planned. Looking over the past few thousand years reveals a depressing picture of wars that begin for limited ends, only to be knocked wildly out of control by unexpected events. This is particularly the case in democracies, where public opinion has a habit of demanding more than is wisely available. In the Peloponnesian War, the Athenians repeatedly passed up opportunities for an advantageous peace, chasing after a victory that turned out not to be possible. In our own case, we passed up opportunities for negotiated peace with a militarily superior Germany in 1916 and 1941. It was only the good fortune—for us, at least - of American involvement that allowed us to scrape two increasingly pyrrhic victories. Will public opinion in American and Britain now accept a clean end to this war? Or will expectations be raised of Mr Blair's better world order?

Otherwise, there are those unexpected events. I am assuming that the relevant Islamic leaders are themselves rational actors. Do they accept that they have won their main point, but that there must also be an armed response? Or will they unleash further terror in the West? If so, we may find ourselves in a general war with a largely unseen enemy. Suppose then that the Chinese take advantage of American preoccupation by invading Taiwan. Suppose further that the Americans find themselves forced to choose between accepting an humiliation that will damage their chance of winning their Islamic war and threatening a nuclear response to China. Or suppose the riots that have already broken out across Pakistan bring down the military government there, and we find ourselves fighting two enemies instead of one. Certainly, it is useful to look at wars as if they were a game of chess, but they do not always unfold as neatly as a game of chess.

But these are possibilities that we must hope can be avoided by a combination of luck and skilful diplomacy. For the moment, it looks as if the world is on the edge of a return to the old balance of power diplomacy that worked with conspicuous success in the century before the Great War. It may strike some as odd, but the world is a safer place when nation states pursue limited ends in the light of their own narrow interests, than when they go on endless crusades for human rights and democracy. If this war is of the former kind, the American and British governments—for what little it may be worth - have my support. If not, we should all get out of the big cities as soon as possible, and look up some of those now quaint Millennium Bug survival guides on how to store food and make our own ammunition.