CHENEY KNEW

In a bunker beneath the East Wing of the White House, Cheney locked his eyes on CNN, chin resting on interlaced fingers. He was about to watch, in real time, as thousands were killed on Sept. 11, 2001.

Previous accounts have described Cheney's adrenaline-charged evacuation to the Presidential Emergency Operations Center that morning, a Secret Service agent on each arm. They have not detailed his reaction, 22 minutes later, when the south tower of the World Trade Center collapsed.

"There was a groan in the room that I won't forget, ever," one witness said. "It seemed like one groan from everyone" -- among them Rice; her deputy, Stephen J. Hadley; economic adviser Lawrence B. Lindsey; counselor Matalin; Cheney's chief of staff, Libby; and the vice president's wife.

Cheney made no sound. "I remember turning my head and looking at the vice president, and his expression never changed," said the witness, reading from a notebook of observations written that day. Cheney closed his eyes against the image for one long, slow blink.

Three people who were present, not all of them admirers, said they saw no sign then or later of the profound psychological transformation that has often been imputed to Cheney. What they saw, they said, was extraordinary self-containment and a rapid shift of focus to the machinery of power. While others assessed casualties and the work of "first responders," Cheney began planning for a conflict that would call upon lawyers as often as soldiers and spies.