It has been rumoured that Pearl was especially interested in any role played by the US in training or backing the ISI. Daniel Ellsberg, the former US defence department whistleblower who has accompanied Edmonds in court, has stated: "It seems to me quite plausible that Pakistan was quite involved in this ... To say Pakistan is, to me, to say CIA because ... it's hard to say that the ISI knew something that the CIA had no knowledge of." Ahmed's close relations with the CIA would seem to confirm this. For years the CIA used the ISI as a conduit to pump billions of dollars into militant Islamist groups in Afghanistan, both before and after the Soviet invasion of 1979.

Senator Bob Graham, chairman of the Senate select committee on intelligence, has said: "I think there is very compelling evidence that at least some of the terrorists were assisted, not just in financing ... by a sovereign foreign government." In that context, Horst Ehmke, former coordinator of the West German secret services, observed: "Terrorists could not have carried out such an operation with four hijacked planes without the support of a secret service."

That might give meaning to the reaction on 9/11 of Richard Clarke, the White House counter-terrorism chief, when he saw the passenger lists later on the day itself: "I was stunned ... that there were al-Qaida operatives on board using names that the FBI knew were al-Qaida."

http://www.guardian.co.uk/september11/story/0,11209,1266512,00.html