"I shall return," General Douglas MacArthur famously promised the Filipino people following the Japanese invasion and occupation of the Philippines in spring 1942. The people there believed MacArthur's vow, and two and half years later, he was ready to embark upon the liberation of these war-torn islands. As James Duffy explains, however, it would not be an easy campaign. The more than 7,000 islands of the Philippine archipelago were the key to taking down the Japanese Empire—and the Imperial forces were prepared to sacrifice every man and every ship to prevent MacArthur from regaining control of them.