Mr Gates was the deputy national security adviser at the White House both before and during the Gulf war, and was therefore in an unparalleled position to relate the deliberations over whether to make the capture of Saddam Hussein one of the US war aims.
Until now the official explanations for not trying to capture Saddam Hussein have been: that US troops would take an unacceptable level of casualties if they drove through to Baghdad; that the Arab partners to the coalition would drop out if the declared war aim - the liberation of Kuwait - were replaced by Western armies invading an Arab capital; that the Bush administration had put its faith - mistakenly it is now clear - in Saddam Hussein being overthrown in a post-war coup by disaffected army officers.
Mr Gates told the Los Angeles Times that the reason they did not seek out President Saddam was the fear that he would go into hiding, as the Panamanian leader, Manuel Noriega, did during the 1989 US invasion of Panama. 'We were all a little shaped by that experience, and Iraq's a hell of a lot bigger country than Panama and we knew a lot less about it than we did Panama,' the newspaper quoted Mr Gates as saying.
'I think there was a general feeling that it would not be difficult for Saddam to flee Baghdad and it would be very difficult for us to try and find him. So you'd end up potentially occupying much of Iraq and then having to deal with the consequences of that.'
Mr Gates also revealed some of the internal workings of the secret intelligence committees that debated what to do about President Saddam. He said that concern about the reaction of Arab allies was less of a factor than 'our own internal deliberations about what our war aims should be'. There had also been uncertainty in the Bush administration as to whether Iraqi military officers would actually overthrow President Saddam after the war.
The decision was taken by a co- ordinating committee between the State Department, the Pentagon and the security and intelligence agencies. 'We specifically decided not to make it (capturing Saddam) a war aim so that we would not set ourselves objectives that we were not confident we could accomplish,' Mr Gates said.