The Japanese Umbrella: Assurance vs Deterrence

Between the important role of extended deterrence in the Nuclear Posture Review and the upcoming Japanese elections, more attention is being drawn to the future of the US/Japan alliance and potential for Japan to develop its own nuclear capability. We began this discussion with an earlier post about an article by Sean Varner.

Yesterday, Varner was kind enough to respond to our post in the comments and elaborate some of his points. I want to touch on a couple of things he said.

First, Varner argues that Japan remains concerned with the specific weapons capabilities of the US vis-a-vis China:

The question of extended deterrence does indeed boil down to capability and credibility. You make a very good point that we may be “leading the witness” in trying to convince the Japanese what we need, but the fact that they’re hearing from both sides of our nuclear debate would suggest to me that they have their own reasons for desiring a certain capability. Their (assumed) assertion to the Strategic Posture Commission that U.S. credibility rests on our “specific capabilities to hold a wide variety of targets at risk, and to deploy forces in a way that is either visible or stealthy, as circumstances may demand” illustrates to me how concerned they are about China.

Second, Varner remains concerned about the potential of Japanese proliferation, especially if the US agrees to reduce its arsenal under START or similar agreements:

Like I said in the initial op-ed, Tokyo could be forced to make the least miserable choice out of a list of bad options. Unsure of the U.S. deterrent while Pyongyang and Beijing grow more provocative would be unacceptable. Developing their own deterrent would result in harsh int’l pressure and a regional arms race. Their only good option at present is to convince the U.S. to maintain a capability it feels it can depend on. But that option may expire with START or later agreements.

It is important to note that the concern over Japanese proliferation is more medium-to-long term than it is short term. In a detailed examination of the conditions that would push Japan to develop nuclear weapons, James Schoff points out that there have been a number of studies conducted and articles written after the North Korean nuclear test in 2006 to assess its impact on Japan and that,

Virtually all of these studies and articles conclude that there is essentially no chance that Japan will pursue an indigenous nuclear deterrent in the near future (v)

Japan is comfortable with its current position. It still retains confidence in the US alliance and fears the consequences of acquiring nuclear weapons. However, it is possible that in the future, Japan's strategic calculus will change.

Varner argues that one potential change that could drive Japan to develop its own nuclear arsenal is additional reductions in the US nuclear arsenal via START that will cause the Japanese to conclude that US capabilities cannot match China. Varner is probably correct that Japan is increasingly worried by China's advancing military capabilities. However, the direct link between nuclear arms control and US deterrence of China seems suspect.

In some ways, Varner is right. Japanese defense planners have attached a symbolic important to certain US weapons. For example, the Japanese see nuclear-tipped Tomahawk cruise missiles as a US capability that is "for them." As a result, a GSN report reported that,

Japan has asked the United States to consult with partner governments before rolling back any nonstrategic nuclear-weapon deployments, according to the news service

This is an example of "leading the witness." In meetings with Japanese officials, US defense planners have built up the importance of certain technologies, like the Tomahawk. As a result, the Japanese think these weapons are way more important than they actually are. The Tomahawk is a good example because it is not even currently deployed, but still seen by the Japanese as an important symbol of US commitment to Japan's defense.

As Schoff explains, the problem is less the capabilities that the US maintains and more the symbolic importance of certain weapons:

Part of the reason for this is that as old symbols of deterrence are phased out, they are being replaced with a diffuse range of more capable (but only vaguely understood) assets, oftentimes deployed from farther away. The assurance effect is less concrete and immediate, though the deterrence effect might actually be stronger, because a potential adversary’s defense planners are paying perhaps the closest attention to the whole array of new capabilities. This helps explain why Tokyo can be underwhelmed with recent developments while at the same time Beijing is alarmed. (23)

Schoff makes it clear that it is possible for the US to simultaneously increase our deterrence of China, while decreasing our assurance of Japan. It is important to recognize the difference between deterrence and assurance. Both deterrence and assurance are made up of a number of factors including capabilities, force posture, and credibility of commitments. However, deterrence refers to how our adversaries perceive these factors, while assurance refers to how our allies perceive these factors.

There are important differences. For example, with deterrence, it can be important to maintain ambiguity. The US uses ambiguity to its advantage when discussing potential retaliation to chemical and biological weapons or whether it relies on launch-on-warning. As a result, potential rivals cannot predict the US reaction and have to assume the worst. However, with assurance, the opposite is true. The less forthright the US is with Japan about our specific capabilities and willingness to defend their county, the more likely Japan will develop an indigenous defense capability.

As a result, it seems like Varner's conclusion that further nuclear arms reductions will cause Japan to nuclearize is not entirely true. Instead, if the US engages Japan in frank and open discussions to explain our new capabilities and the extent of our commitment to defend Japan, they will likely be reassured. It is important that these discussions de-link US extended deterrence from certain capabilities. US capabilities are constantly changing and, in many cases, conventional weapons are as good, if not better, than their nuclear equivalents. The US must build trust and explain the depth of its commitment to defend Japan without pointing to specific weapons. However, it is important that discussions go beyond mere notification. The US must involve Japan in the process before decisions on weapons cuts or force posture changes are made if we hope to earn their trust (as proven by Japan's request that we consult before limiting non-strategic weapons capabilities).

These frank and open discussions will be even more important given the political situation in Japan. In a few days, it is expected that the Liberal Democratic Party (LDP), which has been in power for all but 10 months since the Japanese government was founded in 1955, will lose in a landslide. The rival Democratic Party of Japan (DPJ) will come to power for the first time.

Some argue that the new election could cause problems for the US. Would-be Prime Minister Yukio Hatoyama has called for a foreign policy more independent of the US, which could make it difficult for the Obama administration to maintain a strong alliance.

However, in a recent opinion piece in the Japan Times, Shingo Fukuyama and Hiromichi Umebayashi argue that the DJP will be more receptive to a reduced role of US nuclear weapons:

It is distressing to note that Japan is being used as an excuse to prevent Washington from making an important policy change that would be a step forward toward a world without nuclear weapons. Some argue that a reduction in the role of nuclear weapons would weaken the U.S.-Japan security relationship.
Others, for example former U.S. Defense Secretary James Schlesinger, even suggest that Japan might choose to acquire its own nuclear weapons.
In fact, there are signs of greater flexibility than these people acknowledge. It is widely predicted that there will be a change of government after the Aug. 30 elections and that the Democratic Party of Japan (DPJ), currently the largest opposition party, will win. The attitude to NFU by the DPJ and its potential coalition partners is likely to be quite different from the LDP.
DPJ secretary general Katsuya Okada has suggested that Japan work with Washington to achieve a NFU policy. In response to a questionnaire sent recently to Japanese political parties by disarmament nongovernment organizations, the DPJ said that NFU was an issue that should be discussed with the U.S. government.

While there has been a lot of rhetoric in the campaign, it is unlikely that there will be major policy changes. A Channel News Asia article, quoting Michael Auslin of the American Enterprise Institute, argues that the new Japanese leadership will quickly find out that Japan does not really have an option to replace the US. Instead, the challenge for the Obama administration will be building a relationship with a new ruling government. In some ways, the US will have to start from scratch in developing ongoing dialogue as well as ensuring that Japanese leaders have detailed understandings of US deterrence in East Asia.

More broadly, as the Obama administration continues its pursuit of Global Zero, while attempting to assure our allies that our extended deterrent remains credible, it will be important for administration officials to assure our allies that large nuclear arsenals are not a critical component of our assurance policy. This will allow the US to maintain its alliances, while continuing to move toward a reduced role for nuclear weapons in security policy.