reporter: the americans call for air strikes and they come with thundering force. [ explosions ] we brought in spectre gunships which can put a bullet on every inch of a football field. the amount of ordinance dropped over a period of two weeks almost defies belief. the mountains were rearranged. reporter: from a radio, word of a dead al qaeda fighter. the americans hear bin laden try to rally the men. we hear him apologize to them for having led them to an area where they are having air strikes on them relentlessly. reporter: with bin laden in the crosshairs, berntsen wants u.s. forces sent in to finish the job. in the first two or three
reporter: six years earlier a journalist interviewed bin laden here in a cave turned into a command center. he told me that he feels safe in the caves. he knows the area very well. he knows it is very difficult for anybody to come and follow him there. reporter: but now bin laden is being followed. at that point i only had about 20 americans in the province, you know, working with a couple thousand afghans we had put online. we had paid a number of afghans. the journalists gathered on the mountainside there. reporter: tim lister was part of the cnn team for the war. we outnumbered the number of u.s. personnel on the ground. reporter: the americans call for air strikes and they come with thundering force. [ explosions ] we brought in spectre
s.e.a.l.s would rather die than be captured. at the end of the day it was a leap of faith. reporter: friday, april 29, just after 8:20 a.m., the mission begins. the president gives the go. the president, after a long night s sleep, basically came in and immediately told the staff, you ve got the green light. let s go. reporter: as president obama departs for the tornado-ravaged south, the u.s. military s best-kept secret is under way. the troops were ready and in place. the equipment was ready to go. the plan had been practiced again and again and again. reporter: america s most wanted man may finally be in reach. osama bin laden. the architect of 9/11 had eluded the world s most powerful nation for more than a decade. the trail was quite cold. reporter: former cia director michael hayden recalls the early misfires. most of what he had looked more like elvis sightings than intelligence. reporter: the trail caught fire last august when u.s. intelligence