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Fear and Flashpoints: Why a Japanese Nuclear Rethink is Plausible

In late March this year, presumptive Republican nominee Donald Trump gave a revealing glimpse into what American nuclear policy might look like under a Trump presidency. Speaking at a republican town hall event, Trump made the case that American foreign policy should not focus on halting nuclear proliferation in all instances, conceding that proliferation is “going to happen anyway”. Speaking to the New York Times just a week earlier, Trump gave a remarkably positive assessment of a hypothetical proliferation event in Northeast Asia, arguing that a scenario where Japan obtained a nuclear weapon capability would not be all bad and is also not that unlikely.

It is often easy to dismiss Trump’s statements as merely unthinking and egotistical attempts at generating headline controversy. That said, while Japan has historically endorsed a three pronged nuclear weapons policy of non-possession, non-production, and non-introduction, the idea that it may acquire nuclear weapons in the near to medium term is perhaps not as unthinkable as its anti-nuclear history may suggest.

The first thing to consider is the tense strategic environment that has characterised maritime Northeast Asia in recent memory. Chinese strategic behaviour, described as “creeping maritime expansion”, has been a consistent threat to the stability of the region. Chinese naval strategy seems determined to coerce neighbours into acquiescing to its growing power and maritime claims. This manifested most prominently in the declaration of an Air Defence Identification Zone in November 2013 which covered a large swathe of the East China Sea.

China has engaged in similar efforts in the South China Sea, establishing new zones of military authority with the creation and militarisation of new landmasses through dredging activities. Further, China’s extensive maritime patrols in the East and South China Seas have not always succeeded in being tactically non-threatening. An incident in January 2013 when a Chinese navy vessel directed a fire-control radar at a Japanese Maritime Self-Defence Force ship, as well as its muscular contestation of the Senkaku islands, both illustrate that China has been unambiguous in its willingness to target Japanese interests specifically and to engage in dangerous brinksmanship.

Crucially, Chinese assertiveness has come at a time when several developments have combined to weaken US extended nuclear deterrence over Northeast Asia. First, there is increasing concern that Pyongyang has succeeded in developing a functional Inter-Continental Ballistic Missile (ICBM). Indeed, in April 2015 Admiral Bill Gortney issued the first public statement warning that Pyongyang had successfully wedded the KN-08 missile with a miniaturised warhead.

To the extent that US credible deterrence is based on a cost-benefit analysis of responding to an attack on an ally with a US attack on the adversary, an operational ICBM in the hands of Pyongyang gives it the capability to retaliate against the US, increasing the costs and thus diminishing the credibility of US nuclear assurance to its allies.

Second, while the idealists among Japanese policy makers support nuclear arms reductions under the auspices of the New START agreement, realists argue that the reduction of deployed warheads may reach an extent wherein there is not enough to maintain credible deterrence. Some claim that this threshold will be passed with the conclusion of the New START reductions. Furthermore, there are concerns that excessive arms reductions on behalf of the US and Russia may cause China to abandon minimal deterrence and push for strategic parity.

A final concern is that both China and Russia have been modernising their nuclear arsenals for some time. The US nuclear triad, however, is lagging behind the modernisation cycle of its peers. Considering the trend of China’s behaviour, a newly modernised arsenal may only encourage its assertiveness and stoke Japanese fears. Similarly, an ageing US arsenal may further embolden its nuclear rivals to the detriment of Japan’s security.

While anti-nuclear sentiment in Japan remains strong, considering the success that Shinzo Abe’s conservative Liberal Democratic Party has had in revising previously hallowed limitations on Japanese defence posture, a similar revision on its nuclear policy does not seem out of the question. Indeed, history tells us that Japan has reacted with acute unease in response to perceptions of American abandonment as was the case following President Nixon’s promulgation of the ‘Guam doctrine’ which emphasised greater strategic self-reliance for America’s allies. That a similar perception of abandonment resulting from the weakened state of American extended deterrence may catalyse a revision of Japan’s anti-nuclear principles, is not a completely unreasonable suggestion in the context of the geopolitical environment.

The key takeaway is that the existing strategic and political circumstances may lend weight to a Japanese rethink on its nuclear weapons posture. While a lot still needs to go right for this to occur, the possibility that Japan might develop an indigenous nuclear deterrent no longer seems as remote as it once did. This raises an important question, do Trump’s remarks perhaps reflect a heretofore well concealed but nonetheless sophisticated understanding of global geopolitical dilemmas? We can only hope that the answer is yes.

Henry Overton is an undergraduate BA student at the Australian National University. He is currently completing his Honours in international security studies.

This article can be republished with attribution under a Creative Commons Licence. Please email for more information.

Image credit: Daniel Foster (Flickr: Creative Commons)

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