Scholars and historians will debate for years to come the precise causes and historical forces that produced the sudden collapse of communism at the end of the 1980s. One matter not in dispute, however, will be the earth-shattering role played in the process by Pope John Paul II, the Polish pope. From the moment of Cardinal Karol Wojtyla's election to the papacy in October 1978, he began to shake the very foundations of communism. His first pilgrimage to Poland in 1979 helped undermine government censorship as the Polish people heard the pope talk about human dignity and pray, "Spirit, come...