Max Hastings: Bush's belief in a worldwide Islamist conspiracy is foolish and dangerous.

In the eyes of many Muslims, the actions of Bush and Blair have promoted and legitimised al-Qaida in a fashion even its founder could hardly have anticipated a decade ago.

Bush has chosen to lump together all violent Muslim opposition to what he perceives as western interests everywhere in the world, as part of a single conspiracy. He is indifferent to the huge variance of interests that drives the Taliban in Afghanistan, insurgents in Iraq, Hamas and Hizbullah fighting the Israelis. He simply identifies them as common enemies of the United States.

Almost three years ago he contemptuously challenged the Iraqi insurgents to defy American will: "My answer is - bring 'em on." Today he has widened this bold defiance to embrace a vastly more ambitious range of foes: "He who has one enemy will meet him everywhere."

Far from acknowledging that any successful strategy for addressing Muslim radicalism must include a just outcome for the Palestinians, he endorses Israel's attempt to crush them and their supporters by force of arms alone, together with Israeli expansion on the West Bank. The west faces the probable defeat of its efforts to stabilise Afghanistan, a worthy objective, because of the likely failure of its campaign in Iraq, which began on false pretexts.

There is no chance that the west will get anywhere with the Muslim world until the US government is willing to disassemble a spread of grievances in widely diverse societies, examine them as separate components, and treat each on its merits. America cannot prevail through the mere deployment of superior wealth and military power, the failure of which is manifest. Judicious and discriminatory political judgments are fundamental, and today quite lacking.

The madness of Bush's policy is that he has made a wilful choice to amalgamate the grossly irrational, totalitarian and homicidal objectives of al-Qaida with the just claims of Palestinians and grievances of Iraqis. His remarks on Saturday invite Muslims who sympathise with Hamas or reject Iraq's occupation or merely aspire to grow opium in Afghanistan to make common cause with Bin Laden.

If the United States insists upon regarding all Muslim opponents of its foreign policies as a homogeneous enemy then that is what they become. The Muslim radicals' "single narrative" portrays the entire course of history as a Christian and Jewish plot against Islam.

It is widely agreed among western governments and intelligence agencies that, in order to defeat the pernicious spread of such nonsense, a convincing counter-narrative is needed. Yet it becomes a trifle difficult to compose this when the US president promulgates his own single narrative, almost as ridiculous as that of al-Qaida.