If the decision to pull US forces out of Saudi Arabia had been announced before the war on Iraq, it would have been seen, correctly, as a major victory for Osama bin Laden and his supporters. Al-Qaida began its campaign with the demand for a withdrawal of American troops from the country. Timing the announcement for the aftermath of the war has been clearly calculated to minimise that perception.
The Americans discovered soon after the 1991 Gulf war that the presence of their forces in Saudi Arabia was doing them more harm than good. Alternative locations would have been sufficient for their purposes. But they did not want to leave because their departure would have been seen as a political breakthrough for Bin Laden.
The invasion of Iraq provided an ideal solution. It broke the link between the presence of US forces and the threat from Saddam Hussein. At another level, it eased the American crisis of confidence after the events of September 11, which made the US avoid any decision that might make it seem weak. The removal of Saddam in such a dramatic manner has almost treated this obsession. The decision to leave Saudi Arabia can now appear to have been taken from a position of strength.
Al-Qaida sympathisers see it differently. But the majority would concede that invading and occupying Iraq has made the presence of a few thousand troops in the kingdom a less significant issue. It is also clear that this will not be a real departure. Although troops in uniform will leave, the overall establishment - including bases and non-uniformed personnel - is to stay. More important still is the green light that has been given for the troops to return without fresh Saudi approval.
Nor is the decision to withdraw likely to reduce Muslim hostility towards America. Many Muslims regard US actions since the September events as far more oppressive to them than the presence of their forces in Arabia. The invasion and occupation of Iraq will never be seen as a liberation. The sight of US tanks in Baghdad has been regarded as the most humiliating event for Arabs and Muslims since 1967. Baghdad, the capital of the Islamic Caliphate for 600 years, occupies a central place in the Muslim memory and means more even than Riyadh or Cairo.
After 1998, Bin Laden had in any case gone beyond the aim of expelling American forces from the kingdom to full-scale confrontation with the US. Bin Laden and his supporters can now be expected to see his war as more justified than ever because of the occupation of Iraq.
The US invasion of Iraq has been a gift to Bin Laden. He had argued that Muslim countries are the main target - and Iraq was attacked, not North Korea. Bin Laden argued that the US was bent on occupation, not simply intimidation - and that has proved to be the case. He argued that most Arab leaders, and especially the Saudis, would side with the US against their fellow Arabs - as it has turned out. He argued that Ba'athism and Arab nationalism do not work and that only Islam and jihad can deliver for the Muslims and Arabs. The collapse of the Saddam regime has strengthened that argument.
The course of the conflict also bore out Bin Laden's view that only "asymmetrical warfare" can be effective against such highly advanced military power. US ruthlessness in killing civilians, destroying infrastructure and the encouragement it gave to the destruction of valuable heritage and public records has also bolstered the al-Qaida message. The same goes for US public support for the invasion of Iraq, because Bin Laden has said his problem is with all Americans, not only the government.
What effect will this step have on the stability of the Saudi regime? As is well known, the regime depends on religious legitimacy. It has always breached Islamic teachings, but got away with it by exploiting a loyal religious establishment. The regime thought it could do the same over the presence of American troops. But the result was that the religious establishment itself lost its credibility. That was because Islamic teaching is unequivocal on this issue: non-Muslim troops are forbidden to settle in Arabia. Helping non-Muslims to attack Muslims also makes whoever does so a non-Muslim or "infidel" themselves. The Wahhabi school of Islam, dominant in Saudi Arabia, is particularly unyielding about these two points.
So, given the fact that US forces have been in the country for over 12 years, their departure is not real and that Saudi bases have been used to attack Afghanistan and Iraq, it is now impossible for the regime to recover legitimacy. Prince Sultan, the Saudi defence minister, stupidly destroyed any slim chance of benefit from the US withdrawal by attributing the decision to the US itself.
· Saad al-Fagih is a leading exiled Saudi dissident and director of the Movement for Islamic Reform in Arabia