Why did General Douglas MacArthur struggle to hold a US position of the Philippines?

General Douglas MacArthur struggled to hold the US position in the Philippines primarily due to the overwhelming Japanese military offensive that began in December 1941. The rapid and strategic advances of Japanese forces, coupled with inadequate resources and reinforcements for the American and Filipino troops, severely hampered their defense efforts. Additionally, logistical challenges and the lack of air and naval support further weakened their position, ultimately leading to the fall of the Philippines in May 1942.