Nestled among emerald rice fields and sheltered by the Marine-garrisoned Danang hills, Ap Quang Nam was a showcase village. Passing Marine patrols and their frequent guests were greeted by smiling "hello-okays" from the hamlet's neatly dressed children. Ap Quang Nam's market bustled with black-pajama-clad women, hunkered down to argue prices. One band of men and women sifted gravel to sell to a Danang construction firm—the village's latest self-help project. Each day Navy medical corpsmen held a clinic for boils and bruises, passed out soap, administered an occasional injection.
Ap Quang Nam's mayor was...