After the Taliban fell from power in Afghanistan in the winter of 2001, the hunt for Osama bin Laden began in earnest. One American in particular led the search. He was CIA commander, Gary Berntsen, who had been tracking the al-Qaeda leader for years. In December 2001 he ordered a small group of special forces soldiers and Afghan fighters into the White Mountains close to Pakistan in the hope of cornering bin Laden in the caves of Tora Bora. (Photo: Afghan fighters look out over a smoking valley after a U.S. B-52 aircraft bombed a front line position in the mountains of Tora Bora in north-eastern Afghanistan. Credit: Associated Press)