KANDAHAR, Afghanistan -- Outside the gates of the U.S. military base at Kandahar airport, Jalat Khan selected a stone from the gravel on the shoulder of the road and swallowed it. Then Khan, a jobless wanderer in a turban and robe, did it again. And again. Pretty soon, a crowd had gathered, oblivious to the U.S. Army Humvees rolling out of the base on routine patrols. Even the clatter and roar of American helicopters and transport planes -- part of the daily base traffic that usually turns heads -- couldn't compete with Khan on Thursday, who invited spectators to hear...