Agreed; heck, I'd be more supportive of getting Japan in as a State than the Philippines — reason being that the unconditional surrender terms deprive them of real national self-defense* and statehood would negate a lot of that (as well as ensure via Art 4, Sec 4 that we'd protect them)… of course, given the fedgov's lack of defending the continental States from invasion, that might be just more of an empty a promise than any treaty we have with them.
* I believe that if you disarm someone that you are responsible for that person's safety.
Japan + America we could have been a true Hyper Power.
But then Hawaii wouldn't be raking in the mad dollars from Japanese Tourists flying in to shoot guns :/