CORONADO -- The occupants of the multistory fortress perched at 13,000 feet in the Afghan mountains had no idea they were being watched. For several days in February, the people inside the suspected al-Qaida and Taliban stronghold were monitored by members of a U.S.-led special operations unit called Task Force K-Bar. They reluctantly emerged from the fortress at Ali Kheyl when helicopter gunships swooped overhead in the middle of the night and ordered them out. It was then the U.S. special operations troops breathed a sigh of relief: The operation revealed the occupants of the fortress included 56 children....