For the purposes of this subchapter—

((a)) The term “person” shall include an individual, partnership, corporation, or the Government of the United States.

((b)) The term “United States” when used in a geographical sense shall include the United States, its Territories and insular possessions, and the Canal Zone.

((c)) The term “nationals of the United States” includes (1) persons who are citizens of the United States, and (2) persons who, though not citizens of the United States, owe permanent allegiance to the United States. It does not include aliens.

((d)) The term “Yugoslav Claims Agreement of 1948” means the agreement between the Governments of the United States of America and of the Federal People’s Republic of Yugoslavia regarding pecuniary claims of the United States and its nationals, signed .