STRATEGYPAGE LOOKS AT JAPAN’S MILITARY PROSPECTS:
Japan reprocesses plutonium for its many nuclear power plants, which gives it the ability to make nuclear weapons if it needs to, and it does have a strong space-launch capability (many ICBMs have become the means to launch satellites and other vehicles into space). Japan could have a working nuclear weapons capability in one year should they decide to.
The underlying truth is that at this time, Japan is arguably the strongest power in East Asia – and it is at this point with one hand tied behind its back. Should Japan be pushed to the point where it feels it needs to use all the military power it is capable of generating, it could readily become a superpower in military terms. . . . The only reason Japan is not a superpower is because it has chosen not to pursue that course.
This may change, if the Chinese continue to seem interested in pursuing an expansionist policy.