The predawn hours of March 4, 2002, just below the 10,469-foot peak of a mountain in eastern Afghanistan. Outnumbered by Al Qaeda fighters, Air Force Combat Controller John Chapman and a handful of Navy SEALs struggled to take the summit in a desperate bid to find a lost teammate. Chapman, leading the charge, was gravely wounded in the initial assault. Believing he was dead, his SEAL leader ordered a retreat. Chapman regained consciousness alone,...