WHEN THE BARBARIANS OVERRUN THE STREETS

The giveaway was the yellow diplomatic license plate with the number 64: it announced that the white Toyota Hiace van, making its morning run along Karachi's Shara-e-Faisal Boulevard, was registered to the U.S. consulate. At a red light, two men jumped out of a stolen taxi, and as one stood watch, another fired at the van with an AK-47 rifle. Sixteen gunshots later, Gary C. Durell, 45, a CIA communications technician, was dead, and Jackie Van Landingham, 33, a consulate secretary, was fatally wounded. A third employee, postal clerk Marc McCloy, 31, was shot in the ankle. The gunmen spared the...