MacArthur’s order to fall back to the Bataan Peninsula concentrated the American and Filipino forces and provided them with good defensive lines but it also cut them off from the supply depots scattered about Luzon. (MacArthur initially wanted to fight aggressively so the depots were placed closer to potential Japanese landing zones). LieutGen Homma, the Japanese commander, felt that with the Allies on the run and no US Navy to rescue them, they would be an easy target. If they weren’t then he could just besiege them and starve them into surrender. So he released his best men to accelerate the timetable for the real prize in the South Pacific: Java and the Dutch East Indies. His remaining 60,000 men were facing 80,000 Americans and Filipinos, but were much better supplied and had complete control of the air. But in Malaya, Homma’s peer and rival, Lieut Gen Yamashita, was making steady progress against the British and Commonwealth troops, and he only had less than half what the British had. If Homma didn’t continue to attack, he would be disgraced.

Homma’s men and tanks threw themselves at the first defensive line stretching Abucay in the East to Mauban in the West. The Allies put up tough resistance but with little capacity for reconnaissance operations, and an impassable mountain prohibiting mutual support between the defending corps, the well fed and well supplied Japanese used solid infiltration tactics to establish local superiority at the points of attack. What little counterattack capability the Allies had, including the last horse mounted cavalry charge in American history by F troop 26th Cavalry Regt (Philippine Scouts) led by 1LT Edwin Ramsey couldn’t stop the Japanese. MacArthur abandoned the Abucay-Mauban Line on 22 January 1941.
Under pressure from the Japanese the exhausted and hungry Allies were slow to abandon the line lest the withdrawal became a rout. Homma decided to speed things up, and ordered all of his units to attack. Many Japanese units bypassed the retreating Allies, and drove deeply down the peninsula, some infiltrating well passed the next defensive position, the Orion-Bagac Line. Bypassing the units was a mistake. Recognizing the danger, an adhoc force of American and Filipino troops plugged the gap on 23 January and held the vital Trail 2 open as the galvanized remainder of Allies trudged into the much more easily defended Orion-Bagac Line.

The Orion-Bagac Line was much shorter, and very quickly the infiltrating Japanese found themselves isolated and cut off. As the main Japanese force launched banzai charge after banzai charge against the Allies in order to break through to these “pockets”, the Filipinos took to them with a vengeance, systematically eliminating each one over the next two weeks. Homma attempted and end run with amphibious landings on the southern end of the peninsula but these too were quickly contained. They were initially supposed to trap the retreating Allies, then they were to relieve the pockets, but instead they became pockets themselves, just on the “points” of land jutting into the sea.

The Americans and Filipinos on Bataan at the Battle of Trail Two, The Stand at the Orion-Bagac Line, the Battle of the Pockets, and the Battle of the Points caused Homma enormous casualties. So many so that the Japanese could not continue the offensive. On 13 February 1941, the disgraced Homma ceased operations, dug in, and to his eternal shame, requested reinforcements.

The Japanese took extensive casualties (and would lose one of their best generals), but to the Allies, this small consolation prize couldn’t change the horribly obvious truth that the Americans and Filipinos on Bataan were still doomed.