THE HUNT

A different sort of search requires a new set of tactics

Introduction: Becoming more like him

Finally, after weeks of searching the caves and mountains of Tora Bora for traces of Osama bin Laden, CIA field commander Gary Berntsen believed his men had a good peg on the terrorist. Berntsen called in the big bomb - the BLU-82, a 15,000-pound device the size of a car.

The bomb was pushed out of the back of a C-130 transport plane. It struck with such force that it vaporized men deep inside caves. The devastation spread across an area as big as five football fields, killing numerous al-Qaeda fighters - including, Berntsen believed, bin Laden.

It was three months after the attacks of Sept. 11, 2001, and Berntsen thought, "I've got him now."

Six days later, two of Berntsen's men were listening to a radio they had picked up from a dead al-Qaeda fighter. They heard bin Laden addressing his troops in Arabic. The hunt went on.

Immediately after al-Qaeda's attack, America went after the world's most notorious terrorist with a quick-action injection of cash, commandos and massive firepower.

Within a few months, that first phase of the search for bin Laden would give way to a decade-long manhunt in which the tedious work of analysis and surveillance would eventually bag the target. To find bin Laden, who had declared holy war on the United States in 1996, the Americans needed to think more like him, to absorb the structures and rhythms of a terror network.

The search that ended Sunday with bullets to bin Laden's head and chest was the result of a new approach to finding an elusive target, the product of a few dozen analysts in Langley who refused to accept that their prey may have vanished forever.