Query: What humanitarian concept did Montini see nationalism as violating?
Context: The only foreign diplomatic experience Montini underwent was his time in the nunciature in Warsaw, Poland in 1923. Like Achille Ratti before him,[a] he felt confronted with the huge problem, not limited to Poland, of excessive nationalism: "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.