On April 11, 1963, John XXIII issued the encyclical
Pacem in Terris
, a powerful call for a world in which there were neither victims nor executioners that cemented the pontiff’s reputation as “Good Pope John.” With the world having teetered on the brink of nuclear war during the October 1962 Cuban missile crisis, a papal appeal for “peace on earth” was well received everywhere, including the Soviet Union—although the view in some Vatican quarters that the masters of the Kremlin took the encyclical’s message to heart was rather naive.