Why Japan won't go nuclear
Mira Rapp-Hooper writes that the U.S. alliance will stay Japan's hand:
'[I]t is highly unlikely that Japan will seek its own nuclear arsenal in the foreseeable future. Beyond public opposition to nuclear weapons, which has only increased since the Fukushima disaster, Japan does not yet have reason to believe it needs an independent deterrent. The U.S.-Japan military alliance has strengthened with the passing decades and has proven highly responsive to Japanese security concerns. On several occasions, Japan has reassessed its non-nuclear status, and has always concluded that the U.S. security guarantee is a superior option. There is little reason to believe that Japan will rethink its commitment to that alliance now.'
Michael Auslin doesn't sound as confident:
'To Tokyo, this highlights the continuing importance of its alliance with the U.S. With no close partners in the region, Japan remains reliant on America as the keeper of the peace. It is now watching to see if Washington's "pivot" to Asia results in less focus on Japan's security needs.In fact, while Washington may depend on Japan for military bases, it's wary of being drawn into Tokyo's disputes with its neighbors, particularly over the Senkakus.
After a similar dispute with China in 2010, the State Department reaffirmed that the Senkaku Islands fall under provisions of the mutual defense treaty with Japan, but Washington made clear it expects Tokyo and Beijing to resolve the dispute through negotiation. Washington is willing to give even less support over the Kurile Islands. More broadly, the Pentagon is facing drastic cuts that will make it riskier to get involved in a conflict except for the most serious of issues, like an invasion of Taiwan.
That means Japan will be on its own when it comes to playing dangerous games over these islands. Yet Japan can't simply give up its claims to either group, since that would spur all its neighbors to make demands. Tokyo will have to perform a solo balancing act but expect it to focus more on the growing power in Asia: China.
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Parsing Japan's territorial claims and those from Russia and China is tricky business - a minefield of historical animosity and power politics. The U.S. has to walk a fine line between defending a legitimate principle - that these issues must be settled through negotiation and not brute force - and being roped in to defend Japan irrespective of the merits of the Japanese position.