[bELyVIS]

One thing no one has mentioned is balance. The US and Japan have exported most of their manufacturing jobs to third world countries (China included) and has become more of a service oriented economy. This means that most of the goods are imported and most of the money leaves the country never to come back unless there is a service needed by the exporting country that they cannot provide for themselves. The money leaving is greater than the money coming back eventually ruining the economies of these service based countries. This also impacts the exporting country because there is no money to buy these goods.
China and Japan will never become close. There are too many Chinese (and other Asian countries) that still remember their aggression in the early 1900's. They might act like they are over this, but if you talk to them (even the younger ones who weren't even born then), you can still sense the resentment.
The US and Japan (and China eventually) will all fail if they don't even out their economic bases.