At first, the dust was all people could see—a whirling brown sandstorm rushing toward the center of the village. Soon it was obvious that the dust was being kicked up by a little pickup truck—a white Toyota with six young men riding in the back. Though the setting was southwest Afghanistan, a landlocked nation in central Asia, the truck had been painted with English slogans with the sound of American culture: "Murder Crew" on one side and "City Boys" on the other.

The men in the truck looked different from the other men of the village, too. Instead of wearing the light-colored robes and caps designed to keep people cool in the one-hundreddegree summer heat, the men in the truck were wearing jet black robes with matching silky black or white turbans. The men's turbans had...