This will bee the first time since pearl harbor that any allied forces have really had a chance to stop, breathe for even one second, and dig in. The air is still in japanese hands. This is a war that is not fought mainly by field marshals and generals, but,. as burgerad points out, by captains, lieutenants and sergeants with bayonets and submachine guns. You don't see the enemy sometimes until they're right on top of you. And this poor unit of garrison troops, who were just hoping for a nice, cushy stationing in manila get torn to ribbons by american artillery.
Japan's rising sun goes supernova and engulfs a huge area of Asia and the Pacific. A war without mercy begins to develop infusing the whole conflict with a savage vibe.