That’s true. But keep in mind that Japan was also occupying China with large numbers of men not only engaged in combat against the Kuomintang and Peoples Liberation Armies, but also to deter any Soviet aggression. Britain and Australia both also allocated resources against Japan, not least of which were significant numbers of ground troops. Secondly, the “resources” have to be looked at. I believe in At Army at Dawn, Atkinson states that it took essentially two cargo ships resupply an avg. US division in the Mediterranean (for a certain period of time), North Africa, or Europe whereas in the Pacific it took ten ships, making a quick rolling up of the IJA in say–Manchuria–a very costly, difficult task.
Adm. King, an Anglophobe (people-phobe actually ), pushed for a Pacific “First” strategy in the midst of contentious talks with the British. I believe Marshall and FDR asked him what his plan was, he began to sputter as he had none, which effectively ended any internal debate…