In World War II, the Philippines were considered to be of great strategic importance because their capture by Japan would pose a significant threat to the U.S. As a result, 135,000 troops and 227 aircraft were stationed in the Philippines by October 1941. Luzon was captured by Imperial Japanese forces in 1942 during their campaign to capture the Philippines. General Douglas MacArthur—who was in charge of the defense of the Philippines at the time—was ordered to Australia, and the remaining U.S. forces retreated to the Bataan Peninsula.