There is near unanimity on this within the British intelligence community. Had Britain not participated in occupying two countries, there would have been no attacks and no training trips to Pakistan or elsewhere.
The US intelligence agencies are close to agreeing that the war in Afghanistan has become a disaster. Some of Obama's advisers are recommending an exit strategy. Washington's hawks (backed by Brown) argue that, while bad, the military situation is still salvageable. This may be technically accurate, but it would require the carpet-bombing of southern Afghanistan and parts of Pakistan, the destruction of scores of villages and small towns, the killing of untold numbers of Pashtuns and the dispatch to the region of at least 200,000 more troops with all their equipment, air and logistical support.
The political consequences of such a course are so dire that even Dick Cheney, the closest thing to Dr Strangelove that Washington has produced, has been uncharacteristically cautious when it comes to suggesting a military solution to the conflict.
Al-Qaida, as the CIA recently made clear, is on the decline. It has never come close to repeating anything resembling the strikes of 9/11. Its principal leader Osama bin Laden may well be dead (he did not make his trademark video intervention in this year's US presidential election) and his deputy has fallen back on threats and bravado. Now Gordon Brown appears to have discovered the existence of the long-established Lashkar-e-Tayyaba (Soldiers of Medina).
This is one of the more virulent jihadi groups created by the ISI, Pakistan's security service, in the mid-90s. Its aim (as I pointed out in 2000) was to repeat the mujahideen's successful war against the Russians in Afghanistan by opening a new front in Indian-held Kashmir. It could not exist without the patronage of the army. It had a membership of 50,000 militants, foot-soldiers trained in camps in Pakistani-controlled Kashmir, bankrolled by the Saudis and the Pakistani government. Teenagers are recruited from poor families, while state payouts for martyrs help fund the organisation.
After 9/11 Pervez Musharraf sidelined them and funding was drastically reduced, but they were not disbanded. Were they involved in the assault on Mumbai? Possibly, but they could not have acted on their own. They needed help inside India, a fact the Indian elite and its western apologists shy away from.
Why should it be such a surprise if some of the perpetrators are Indian Muslims? There has been much anger within the poorest sections of the Muslim community against the systematic discrimination and acts of violence carried out against them, of which the 2002 anti-Muslim pogrom in Gujarat was only the most blatant.
Add to this the continuing sore of Kashmir, which has for decades been treated as a colony by Indian troops with random arrests, torture and rape an everyday occurrence. Conditions have been much worse than in Tibet, but have aroused little sympathy in the west. Being tough on terror but not on the causes of terror is, as we have seen since 9/11, a road to nowhere.
guardian.co.uk, Sunday 14 December 2008 16.19 GMT