American Military History, Volume 2 by Richard W. Stewart

Only in the Philippines, almost on Japan's southern doorstep, was the timetable of conquest delayed. When the Japanese struck, the de- fending forces in the islands numbered more than 130,000, including the Philippine Army, which, though mobilized to a strength of ten di- visions, was ill trained and ill equipped.

Of the U.S. Army contingent of 31,000, more than a third consisted of the Philippine Scouts, most of whom were part of the Regular Army Philippine Division, the core of the mobile defense forces. The Far East Air Force before the Japa- nese attack had a total of 277 aircraft of all types, mostly obsolescent but including 35 new heavy bombers.