MacArthur ordered the mobilization of the Philippine Army beginning on 1 September 1941. Elements of 10 Filipino reserve divisions were to be called into the service of the United States Army by 15 December. Battalions were not organized by the time of the Japanese invasion in December. However, a force of a hundred thousand or more Filipinos was raised. on
Luzon On 14 August Brigadier General
Leonard T. Gerow argued that the Philippine Department could not resist a Japanese attack. He thus recommended that the Philippines be reinforced with
anti-aircraft artillery, modern aircraft and tanks. On 16 August, MacArthur was informed that by 5 September he could expect the
200th Coast Artillery Regiment (AA), the
192nd and
194th Tank Battalions and a company of the
17th Ordnance Battalion. On 5 September Marshall asked MacArthur if he wanted a
National Guard Division, probably the
41st. MacArthur replied that he did not need any additional divisions. He also stated, "Equipment and supplies are essential. If these steps are taken, I am confident that no such backing, the development of a completely adequate defense force will be rapid." During September and October, in addition to the above-mentioned reinforcements, MacArthur received the 192nd Tank Battalion and 75
self-propelled 75 mm guns. MacArthur strove to reorganize the
Philippine Division from a
square into a
triangular formation. This plan involved shipping in an American infantry regiment and or complementing Stotsenburg and allow USAFFE control of 2 American combat teams. These plans also involved the formation of four tactical commands, each of
corps strength, along with various additional support units. By November the War Department had approved additional reinforcements of 1,312 officers, 25 nurses and 18,047 men. The
34th Infantry Regiment was scheduled to ship out from San Francisco on 8 December 1941. By 5 December fifty-five ships were en route from San Francisco carrying 100,000 ship-tons of cargo to the Philippines. On board were the personnel and equipment of the 26th Field Artillery Brigade, including the 147th Field Artillery, 75 mm, Truck Drawn, Regiment of the
South Dakota National Guard; the 148th Field Artillery, 75 mm, Truck Drawn, Regiment of the
Idaho National Guard and the 2nd Battalion of the 131st Field Artillery, 75 mm, Truck Drawn, Regiment of the
Texas National Guard. These units were diverted to Hawaii and assigned to its defenses. When the Japanese
attack on Pearl Harbor took place, there were several air elements en route. This included 52
A-24 Banshee dive bombers of the
27th Bombardment Group, eighteen
P-40s of the
35th Pursuit Group, 340 tons of bombs and 9,000 drums of
aviation fuel. There were also two light field ground echelons of the
7th Bombardment Group, which arrived in the Philippines and were relocated to Mariveles after the evacuation of Manila. The air echelon squadrons of the 7th were en route to the Philippines and arrived in Pearl Harbor on the morning of 7 December 1941. They consisted of 9th, 463rd, 492nd, and 493d Heavy Bombardment Squadrons. The air echelon was diverted back to the US and then routed to
Java through
Australia. ==Material and training inadequacies==