Imagine the scene on May 25, 1986. In the Midwest, 5,000 Americans are marching together for disarmament. The huge procession, which set out from Los Angeles for Washington on March 1, treks across the flatlands pursued by television cameras, supply trucks and spectators. At the same time, another awesome spectacle is taking shape: from one coast to the other, people are lining up side by side and clasping hands to form a huge human chain against hunger.
These two events are not mere pipe dreams. Encouraged by the interest in social causes demonstrated by last summer's Live Aid concert for African...