Japan getting nuclear deterrence?

How much plutonium (Pu) does Japan exactly own? How are
Japan rockets doing? Is the Ballistic missile enough in
tomorrow's world? What if Japan becomes nuclear?

Here is an expert view on the last question :

"Japan sees little reason to develop nuclear weapons. I
would note, however, that it is possible to construct an
equally compelling logical argument that Japan should
develop a strategic deterrent... From a US perspective,
the current situation has some advantages. The Japanese
are looking to us more than ever for support, and are
willing to do more than ever in response. At the same
time, there are some worrying trends - especially in
connection with the increasingly emotional disputes over
history, the contested territories around Japan - the
Northern territories/Kurile islands, Takeshima/Tokdo and
Senakaku/Diaoyutai, as well as the abductees. There may
be some risk that for the first time in the history of
the MST system that it is the United States that faces
the threat of entanglement through its strategic
relationship with Japan, and not the other way around.
At the same time, the potential costs of disappointing
Japan on these issues may also be going up. How the US
should respond to these trends - whether it should
ignore them and reap the benefits of Japanese isolation,
or whether it should try - if perhaps only indirectly -
to mediate some of these disputes - is an issue..."
Thomas Berger Boston University (NBR forum extract)

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