SCAP, an acronym used several times in the movie, stood for "Supreme Commander of the Allied Powers." This was not only the title given to Gen. Douglas MacArthur, head of the Occupation forces, but was also used to refer to the offices of the Occupation - a staff of several hundred U.S. civil servants as well as military personnel who administered the Occupation of Japan.
This was the first movie allowed to film in post-war Japan.