I have been informed by the members of this forum that the Cardinal of Buenos Aires, Argentina would indeed be well versed on internal partisan politics in the United States. Probably reads The Hill and watches the Sunday Morning Talk Shows.
Nobody said a word about internal politics, the President and vice-president and a Speaker of the House were mentioned, you might not read much, but a powerful, high ranking man in Argentina who was in line to be Pope, would probably at least read a daily newspaper.
It is natural that a democrat president would choose the two leading Catholic politicians in America, from his own party, and the party supported by Catholic voters.