During the Great Depression, Franklin Roosevelt used silver to bolster America's economy, but this move weakened China, and facilitated Japan's rise to power before World War II. In the 1970s, the world's richest man Nelson Bunker Hunt went on a silver-buying spree and triggered a financial crisis that left him bankrupt. What makes silver so desirable, and so volatile? Tracing its history, William Silber explains how investors come under silver's thrall, and how silver still guides economic and political decisions in the 21st century.