This is likely insignificant, yet gives some hope. Japan may yet refrain from becoming a pawn, as it would surely be obliterated in a conflict with China. Unfortunately, this is probably but a squabble over blame for imperial incompetence.
Cup half full: either Japan is incompetent or ths US was and is trying to pin the blame on Japan, which will push them away. It could also be a pretext to warn Japan it can be dropped military in an attempt to draw them in, a sort of threat or loyalty test. Either way, imperial disunity favors multipolarity and AES.
Japan, despite its recent violent history with China, Russia, and Korea, has infinitely more to gain from becoming closer to those countries than being a sacrifice for the United States.
Pretty much any country would have more to gain from becoming closer to their actual neighbors over the USA. Except for neighbors of the USA