whatever. certainly not 100% clr identification of osama bin laden. reporter: there is no smoking gun, no photograph of bin laden, just a tall shadowy figure in a compound that arouses suspicion. still, the odds are good enough for panetta to make a case to the president. i think the argument was this was the best chance we have ever had. the odds have never been higher and if we don t take this opportunity, the odds may never be this good again. reporter: panetta tapped vice admiral william mccraven to hatch an action plan. three options are put on the table. one of them was to just go in and bomb it, obliterate it. the problem with that is you probably wouldn t have a body left and you couldn t show evidence that osama bin laden was really there. the next option was to send in an unmanned drone with a
s.e.a.l.s would rather die than be captured. at the end of the day it was a leap of faith. vi . 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 cy director michael hayden recalls the early misfires. most of what he had looked more likele elvis sightings than intelligence. reporter: the trail caught fire last august when u.s. intell