This may be what you think: John Paul II was the conservative Pope. His pontificate was marked by a resurgent Roman Catholic traditionalism, setting the church against liberalizing forces of all kinds. John Paul II is remembered above all for shoring up structures of the past.
This is wrong. John Paul II boldly presided over the maturing of political and theological revolutions in Catholicism. Perhaps despite himself, he was a Pope of change, accomplishing two radical shifts--one in the church's attitude toward war and the other in its relationship to the Jewish people. Taken together, those represent the most significant change in church history, and they lay the groundwork for future changes that could well go beyond what this Pope foresaw or even wanted. In each case, John Paul II brought to completion a movement that was begun by his predecessors John XXIII and Paul VI, the Popes of the Second Vatican Council.
In 1965, the Second Vatican Council issued Dignitatis Humanae, commonly referred to as a declaration on religious liberty. But what made this document revolutionary was its total renunciation of the use of coercion in defense of the truth. It overturned a tradition of sanctioned violence that went back to Constantine and St. Augustine. Paul VI made its meaning explicit by going before the U.N. General Assembly to declare, "No more war! War never again!" This was a reversal of Pope Urban II's 1095 call for the Crusades: "God wills it!"
John Paul II made the renunciation of coercive force the political center of his pontificate. His stout opposition to Soviet communism was built around nonviolence, and his dramatic support of the Polish resistance movement was key to its firm commitment to nonviolence too. Because the democratic opposition behind the Iron Curtain remained peaceful, Mikhail Gorbachev, in the climactic months of 1989, was able to respond to it peacefully. John Paul II is often credited with a crucial role in the fall of communism, but his role, against the expectations of all "realists," was defined by its nonviolence. War never again!
No sooner had the Berlin Wall come down in November 1989 than the U.S. launched the first of its numerous post--cold war wars by invading Panama in December. John Paul II denounced that invasion, a position he would repeat every time the U.S. sent bombers and troops abroad. The Vatican opposed the Gulf War in 1991, the NATO air war against Serbia, the U.S. campaign against Afghanistan, the invasion of Iraq in 2003--the entire spirit of "Crusade" that animates the war on terrorism. The Roman Catholic Church under John Paul II made its opposition to war as clear as a bell, even if in Washington this aspect of the Pope's legacy was steadfastly ignored.
The second revolution brought to completion by John Paul II is in the church's relationship to the Jewish people. Again, the shift began with Vatican II. The 1965 declaration Nostra Aetate famously renounced the "Christ killer" slander, the Gospel charge that the Jews are guilty of the murder of Jesus. This was the source of Christian contempt for the Jewish people, a tradition that the Nazis brought to the perverse conclusion of the Holocaust.