Battle of Bataan - War Plan Orange-3

War Plan Orange-3

After securing the beachheads, the Japanese launched a massive pincer attack and the three PA divisions assigned to contain the beachhead were pushed back by the invading forces. In the face of this onslaught, Gen. MacArthur realized that the beachhead defense plan had failed. On December 26, he notified his commanders that War Plan Orange-3 (WPO-3) was now in effect, thereby reactivating a prewar plan to defend only Bataan and Corregidor in a delaying action. A fighting retreat by units to the Bataan peninsula, whereupon the defending forces, in accordance with WPO-3, would regroup and hold out for six months, at which time the plan assumed (but did not specify) that relief would arrive from the United States. They hoped that with this change in strategy, the Japanese invasion plans might be altered.

The concept of WPO-3 was to delay invading Japanese forces until the U.S. Pacific Fleet could be mustered at full strength and fight its way to the Philippines. At the Bataan peninsula, with its defensive terrain, and backed by artillery from the harbor defenses in Manila Bay and the nearby island fortress of Corregidor, the defenders were expected to hold out until reinforcements arrived. The U.S. Navy had estimated that the Pacific Fleet would need two years to fight its way across the Pacific, but in any case, with the Pacific Fleet having been crippled at Pearl Harbor, no aid would be forthcoming.

Due to MacArthur's decision, with tacit approval from Washington, to change the plan under War Plan Rainbow 5, it was ordered that the entire archipelago would be defended, with the necessary supplies dispersed behind the beachheads for defending forces to use while defending against the landings. With the return to War Plan Orange 3, the necessary supplies to support the defenders for the anticipated six month long defensive position were not available in the necessary quantities for the defenders who would withdraw to Bataan.

Meanwhile, Manuel L. Quezon, the president of the Philippine Commonwealth, together with his family and government staff were evacuated to Corregidor along with MacArthur's USAFFE headquarters on the night of December 24, 1941, while all USAFFE military personnel were removed from the major urban areas. That same day, Manila was declared an open city, and Japanese forces occupied it on January 2, 1942.