THE atmosphere at the White House was “surreal” as America waited for war.

After days of frenetic activity, the game plan seemed clear, almost predictable: the deadline for Saddam to leave Iraq would expire, President Bush would declare war, and then, hours or days later, the bombs would begin to rain on Baghdad in their thousands.

“Everything has ground to a halt,” one member of the presidential staff reported from inside a White House sealed off by police, where the President had hunkered down in the world’s largest bunker.

Then, on Wednesday afternoon, the plan changed abruptly and utterly. George Tenet, the head of the CIA, called President Bush to say that he had just received fresh intelligence from a source in Baghdad that offered a chance of ending the war before it even started with a single, massive home run: the CIA had a “fix” on the whereabouts of Saddam Hussein.

America’s “War Cabinet”, the circle of advisers that has surrounded President Bush since the confrontation with Saddam began, went into an immediate huddle: the Vice-President Dick Cheney, Donald Rumsfeld, the Defence Secretary, Condoleezza Rice, the National Security Adviser, Colin Powell, the Secretary of State, General Richard Myers, the Chairman of the US Joint Chiefs of Staff, and Andrew Card, the White House Chief of Staff.

Mr Tenet, emphasising that there were limits to the reliability of his information, laid out his plan. US Intelligence has known for years that Saddam seldom spends a night in any of his large presidential palaces, but rather moves around from one apparently ordinary building to another, randomly chosen at the last moment. Saddam, possibly with his two sons and several other senior Iraqi leaders, might all be holed up in a bunker beneath a building in a complex in the southern outskirts of Baghdad, Mr Tenet reported.

If the US struck quickly, then Saddam and his entourage might be wiped out, ending the conflict with a single, decisive blow. Saddam has spoken often of martyrdom in the past few days: here was a chance, albeit a slim one, to grant his wish. Saddam was expected to stay in the bunker for the next few hours, Mr Tenet told the President. The longer the delay, the more likely that Saddam would go to ground elsewhere.

The Americans have a vast array of signals intelligence and reconnaissance satellites, as well as airborne surveillance platforms, such as the unmanned Predator, watching and listening over Iraq in the hunt for Saddam, but this information came from a human intelligence source.

There was no guarantee, Mr Tenet emphasised, that an opportunity such as this would present itself again.

A British military official said: “If he was in there and he’s dead, then it was a very good idea. The intelligence was good enough to go on.”

President Bush listened in silence. In 1991 his father had repeatedly tried, and failed, to target Saddam. Then there had been the missed, and much-rued opportunity to kill Mullah Omar at the start of the conflict in Afghanistan.

After nearly four hours of listening to his advisers, President Bush turned to Mr Rumsfeld at 7.12pm Washington time and said: “Let’s go.”

He then signed the “execute order” authorising the attack, now altered to start with the targeting of Saddam. The President then retired with his chief speechwriter, Michael Gerson, to add the finishing touches to his planned television address to the nation.

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