On December 17, 1903, the Wright brothers flew the first heavier-than-air, piloted machine. They travelled 120 feet and were airborne for 12 seconds. That feat of engineering imagination changed the world. But it was morally neutral – neither good nor evil. It simply was. Later, others would imagine morally good applications of that technology – transporting the sick to hospitals, putting out fires, rescuing people in danger. On September 11, 2001, however, nineteen terrorists imagined evil. They, too, changed the world. Imagination is powerful. It can create enormous good. It can unleash hell on earth. It has to be taught how to behave.