By day, Pakistani troops stake out a hilltop shelter built of mud and stone, peering through binoculars at the narrow gullies and expanse of plain below. At night, they climb into four-wheel-drive pickup trucks and patrol the unpaved tracks along the Afghan border — round-the-clock vigilance aimed at catching Taliban and al-Qaida militants. Stung by accusations by the Afghan government that militants find a safe haven in this desolate region, the Pakistani military gave journalists a rare look Friday and Saturday at their border operations. Diplomats and officials from 17 countries were given a separate tour farther north. Full Story