wrote: "This form of nationalism treats foreigners as enemies, especially foreigners with whom one has common frontiers. Then one seeks the expansion of one's own country at the expense of the immediate neighbours. People grow up with a feeling of being hemmed in. Peace becomes a transient compromise between wars." He described his experience in Warsaw as "useful, though not always joyful". When he became pope, the Communist government of Poland refused him permission to visit Poland on a Marian pilgrimage. Roman Curia His organisational skills led him to a career in the Roman Curia, the papal civil service. On 19 October 1925, he was appointed a papal chamberlain in the rank of Supernumerary Privy Chamberlain of His Holiness. In 1931, Pacelli appointed him to teach history at the Pontifical Academy for Diplomats; he was promoted to Domestic Prelate of His Holiness on 8 July of the same year. On 24 September 1936, he was appointed a Referendary Prelate of the Supreme Tribunal of the Apostolic Signatura. On 16 December 1937, after his mentor Giuseppe Pizzardo was named a cardinal and was succeeded by Domenico Tardini, Montini was named Substitute for Ordinary Affairs under Cardinal Pacelli, the Secretary of State. His immediate supervisor was Domenico Tardini, with whom he got along well. He was further appointed Consultor of the Supreme Sacred Congregation of the Holy Office and of the Sacred Consistorial Congregation on 24 December, and was promoted to Protonotary Apostolic (ad instar participantium), the most senior class of papal prelate, on 10 May 1938. Pacelli became Pope Pius XII in 1939 and confirmed Montini's appointment as Substitute under the new Cardinal Secretary of State Luigi Maglione. In that role, roughly that of a chief of staff, he met the pope every morning until 1954 and developed a rather close relationship with him. Of his service to two popes he wrote: When war broke out, Maglione, Tardini, and Montini were the principal figures in the Secretariat of State of the Holy See. Montini was in charge of taking care of the "ordinary affairs" of the Secretariat of State, which took much of the mornings of every working day. In the afternoon he moved to the third floor into the Office of the Private Secretary of the Pontiff. Pius XII did not have a personal secretary. As did several popes before him, he delegated the secretarial functions he needed to the