Why do they hate us so much? Along with the shock, anger and grief comes this question. What makes men execute an atrocity on the scale of those of September 11th? To these questions, many offer two answers: their poverty and our policies. Poverty fuels desperation; our policies stoke humiliation. Desperation and humiliation breed terrorism. The answer is to end the poverty and change the policies.

In its na∩ve form, this view is implausible. The people who carried through this attack are far from poor. Many originate in Saudi Arabia, a relatively wealthy oil state. Equally, the west can do little to assuage such enemies, short of disappearing from the region, if not from the world. Osama bin Laden and his associates wish to expunge the "crusader presence" from Islamic holy places and restore the golden age of Islamic supremacy.

The aim is not peace with Israel, but its annihilation. By confirming the Israeli presence, a peace agreement may just as well increase the risk of terrorist attacks on western targets as reduce it.

The humiliation and rage that spawn what President George W Bush called terrorist groups "of a global reach" are real. But they are the result of a historic failure, not of recent events. We are eating the fruit of three centuries of bitterness between a dominant west and an enfeebled Islamic world.

Western power has transformed or destroyed traditional patterns of life everywhere. Yet nowhere has the rise of the West - of which the US is the contemporary avatar and Israel a humiliating symbol - posed a bigger challenge than for Islam, for two reasons.

Firstly, for a thousand years the Islamic world thought itself more powerful and more intellectually sophisticated than Christendom. Secondly, western ideas of democracy and sexual equality conflict with Islam's traditional practice.

Anatole Lieven, a senior associate of the Carnegie Endowment for International Peace, judges that "with the exception of some of the oil-endowed Gulf states and, to a limited degree, Turkey and Malaysia, every single Muslim country has failed to enter the developed world".

The position is grim. Last year, according to the World Bank, the average income in the advanced countries was $27,450 (€29,750), at purchasing power parity, with the US on $34,260. Israel's income per head was $19,320.

Against this, the average income of the historic belt of Islamic countries stretching from Morocco to Bangladesh was $3,700. If one ignores the case of the oil exporters, not one had incomes above the world average of $7,350.

Turn then to economic policy. According to World Audit's index of economic freedom for 2001, the highest ranks (out of 155 countries) were 42nd, for Kuwait, and 48th, for Morocco. Most of the countries were ranked among the most restrictive in the world.

Again, in the well-known Freedom House evaluation of political liberty, just five of these countries (Bangladesh, Jordan, Kuwait, Morocco and Turkey) were judged even partly free. The rest were simply "not free".

Western ideas of political organisation and economic policy have been resisted or rejected. The countries of the Islamic belt are not just poor, but are falling behind other developing countries. In 1950, Egypt and South Korea had much the same standard of living. Today, South Korea's is almost five times as high. India's standard of living is now almost half as high again as Pakistan's.

The failure of the core countries of the Islamic world to match the Industrial Revolution is not surprising. Apart from the political, social and ideological differences from the West, they lacked fast-running water, coal and iron. Then western imperialism entered the region, depriving it of the capacity for an autonomous response.

The last half-century has been a different matter. If one puts to one side the special case of Turkey, the principal attempts at modernisation were made by socialist regimes, which failed. Now the region lives with the consequences - a resurgent fundamentalism and the often repressive reaction of western-supported regimes.

Western policymakers face harsh realities. There are initiatives the West can take but it cannot make the region rich or politically stable. It cannot secure accommodation between Islamic traditions the modern world. All it can do is the best it can with the world that there is - and endure.