possible if japan see herself as the tip of spear for the US. also what should not ber discounted is the psychological enemity between the chinese and japanese mind. Japan see themselves as superior than the chinese as a race ever since their industrialised era as has remains so that way, esp when they rose so fast into a developed nation post ww2. china lost all 3 major wars with japan. So when China's industrial output surpassed Japan's in 2009, it triggered a line within the Japanese mindset. Call it envy, jealousy. For the Chinese, losing all 3 major wars to Japan has cast a mental shadow onto them. At some point, China will have to 修理 Japan to be free from their Century of Humiliation shadow.
Well, the Japanese has NOT been known to have done that. Japan, in fact, has always been a very opportunistic and self-serving country. This is neither praise nor criticism. In fact, it is good for China that Japan behaves rationally, and is cool headed in their narrow-minded pursuit of self-interest. The Japanese are NOT part of the West in the terms of culture. They don't have a evangelist zealotry. What they do have is hunger for resources and self preservation.
The West might be impossible to deal with, because they could see China's rise as the end of their supremacy. They could hold their supremacy so dearly, that they would consider it the end of their existence once that supremacy is lost. Japan, not so much. Japanese culture is used to not being the overlord of the region (or of the world). In fact, Japan culture has much more experience being a great power in a region (or the world) where they deal with a superpower. Japan is actually much better at this game, than they are at being no. 1 in the region (or the world).
Of course, being opportunistic is also their downfall, in a sense that they are in fact always observing and waiting for an opportunity. Right now, China, Russia and the US are all strong. Japan, being in the middle, will try to stay as neutral as they could, in order not to become cannon fodder of the quarrels between the big three. However, if situation changes, and the big three are no longer strong and overreaching, the Japanese will take the opportunity to expand and invade.
In conclusion, one thing I have always believe about the Japanese is that eventhough they are somewhat strategically short-sighted and opportunistic, they are not a irrational people. In fact, they are perfectly ration and self-serving. This kind of country is actually very easy to get along with.