The U.S. citizen killed by a missile launched from a pilotless drone aircraft over Yemen was the ringleader of an alleged terrorist sleeper cell in Lackawanna, N.Y., administration officials said yesterday. Kamal Derwish, one of two unindicted co-conspirators in the Lackawanna case, died along with the intended target of the attack, senior al Qaeda leader Abu Ali al-Harithi, who is accused of masterminding the October 2000 attack on the USS Cole in which 17 sailors died. These two men and four others were traveling in a car outside the Yemeni capital of Sanaa when they were hit by a Hellfire...