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Ayumi Teraoka on Japan’s Military Development, Response to a Taiwan Contingency, and China Policy

East Asia scholar Ayumi Teraoka talks to CACR about how evolving strategic concerns, legal considerations, and domestic political factors affect Japan’s defense policy and alliance with the United States. This interview is edited for clarity and length. (October 4, 2022)

Ayumi Teraoka is an America in the World Consortium Post-Doctoral Fellow at the University of Texas at Austin. Her research focuses on coercive diplomacy, alliance politics in the Indo-Pacific, and Japanese foreign policy and national security. In her dissertation, which is now a book manuscript project, Ayumi examines the interactive effects of U.S. alliance management efforts and China’s attempts to weaken U.S. alliances from both historical and contemporary perspectives. Previously, she worked at the Center for Strategic and International Studies and the Council on Foreign Relations in Washington, DC from 2013 to 2017. Her writing has appeared in The Japan Times, Foreign Policy, The Diplomat, and the Georgetown Journal of Asian Affairs, among others. Ayumi holds a Ph.D. and an M.A. in Public Affairs from Princeton University, an M.A. in Asian Studies from Georgetown University, and a B.A. in Law from Keio University.


How would you describe the state of Japan-US relations right now?

If I were to describe the state of Japan-US relations right now, I think it is in very good shape. There is enormous public support in both countries for the alliance. One of the polls that a lot of experts look at is the Cabinet Office public opinion polling on foreign policy in Japan, and this year it shows that 98.2% of Japanese public respondents said the relationship with the US is important for the two countries and for the Asia-Pacific region. 98.2% is kind of an incredible number in any public poll in any open, free, democratic society, so that’s how strong the support is for the Alliance. And I think there are also different polls on the American side, but I think views of Japan are also very positive in the United States. And if you look at the history of the two countries, one adversarial part of the relationship was economic and trade conflicts, but that has subsided into the background since the early 1990s. The threat perceptions of external actors like North Korea or China are also converging. So the relationship cannot be better.

However, I think one of the dangers of the relationship being in a positive state is that people might get complacent and it might consequently fail to capture public or government attention and resource mobilization to make that alliance actually function in a more high-intensity environment. In my view, this is not the time to be complacent about it; it is actually at a critical stage to take the alliance to the next level. There still needs to be a lot of work before the alliance can turn into something that can be ready for combat. The two countries have obviously fought against each other before, but they have never fought alongside each other in combat. There’s no joint command between the two countries. So when we think about the future, there is still a lot of homework for the two countries.

Japan has historically had a high turnover of prime ministers. Does that pose an institutional challenge to the United States and Japan in navigating the alliance, or can it be dealt with below the highest level?

I would say that there isn’t much divergence among various leaders in Japan about the importance of the alliance. So I wouldn’t be too worried about different leaders coming in to propose different directions in foreign policy. When the prime ministers change, however, their security teams also change, even if there is some continuity among government officials in the Ministry of Foreign Affairs and the Ministry of Defense who also help sustain the relationship. And I think such changes of teams do pose a challenge or slow the pace of coordination when the two countries want to engage in deeper conversations about long-term planning. So that’ll definitely be a problem.

I think the last time that any leader brought up a new direction for foreign policy toward the United States was 2009, perhaps, when Prime Minister Yukio Hatoyama came in from the Democratic Party of Japan, which kicked the LDP out of power, and he wanted Japan to have a more equal relationship with the United States without defining what “equal” means. He also started advocating replacing the current agreement to relocate the base in Futenma, Okinawa to Henoko, also in Okinawa, with a proposal that it be out of Okinawa prefecture. So that was irregular. But the lesson from that period was that he really harmed Japan’s relationship with the United States, and the public in general didn’t reward Hatoyama for proposing those kinds of policies.

After Hatoyama, there’s an even deeper understanding that no matter who comes into the office, the alliance is something that politicians shouldn’t be playing with for domestic political purposes or any individual desires on policy directions.

You mentioned that on the military side, there’s a lot more work that’s needed to get Japanese and US forces to work together in combat. What are the obstacles to that? Why is there no joint command?

There’s no joint command for a few reasons. First, Japan didn’t even—and still doesn’t, depending on interpretations—officially have a military after WWII. The Japanese have the peace constitution which restricts the use of force and, under this constitution, the self-defense forces started as a police organization, not a military, and evolved into the current state. This is why the self-defense forces still retain some organizational features of the police force that restrain the use of force, making it hard to operate alongside other foreign militaries.

And moreover, during the height of the Cold War, there was a fair amount of reluctance on the Japanese side to be too integrated with the United States military due to widespread anti-war sentiment and the risk of entrapment into multiple wars the United States was engaged in in Asia. So there was little incentive for the Japanese side to have a joint command with the United States.

But now they are facing adversaries who threaten Japan’s own national security, and therefore there are now real possibilities in which the Japanese want their self-defense forces to operate effectively with the U.S. military to counter a shared adversary. The fact that the two forces are not integrated to the extent that other US allies are with the US military is now raising some questions about joint operations in combat, which, as I said before, the two countries have never conducted before.

I think there’s been a little bit of discussion in the past year about coming up with a joint operational plan for a Taiwan contingency. Have they made any progress on that front? What are the obstacles there?

I am not sure what the stage of planning is. There may be quiet discussions over joint planning, but again, that’s probably confidential secret-level conversations. On the public level, Japanese members of the Parliament are engaging in a series of simulations and wargames over Taiwan in a very public manner, talking about and sharing the results with the public. So there’s an extensive public discourse about possibilities of a Taiwan contingency in Japan today. And I’m sure—and I hope that—at more private levels, government officials are having deeper-level conversations.

In the last year or so, Japanese officials have been speaking more publicly about the importance of Taiwan to Japan’s security, and that’s something that’s gotten attention in the China-watching community. People that I’ve interviewed have had conflicting assessments of Japan’s willingness to actually take part in a Taiwan contingency. What are your thoughts? Do you agree with people who think Japan is very unlikely to become involved in a war over Taiwan, or is that within the realm of possibility?

I definitely see a possibility of Japan being involved in contingency around Taiwan, but I am not so sure if Japan is willing to defend Taiwan on its own.

There are largely two questions when thinking about Japan’s "taking part” in a Taiwan contingency. One question is whether Japan would allow U.S. forces to use bases in Japan if there were a contingency around Taiwan. For the United States, access to bases and facilities in Japan would be critical. Under the U.S.-Japan Mutual Security Treaty’s Article Six, Japan agrees to grant the United States the right to use its bases and facilities in Japan for the purpose of maintaining peace and security in the Far East, which includes Taiwan. But this is also paired with another agreement that there would be prior-consultation if the United States were to indeed engage in combat operations in the region, directly from the US bases in Japan. The Japanese government’s official position has been that when the United States engages in such prior consultation, the Japanese will retain the right to say either “yes” or “no” but still judge based on the understanding that “the maintenance of peace and security in the Taiwan area” is “a most important factor for the security of Japan.” There is still ambiguity about how the prior consultation will take place between the two countries and whether Japan can realistically say no and deny the access to the United States. I would say that if Japan were interested in keeping the alliance with the United States in the future, even after the outbreak of war over Taiwan, Japan would likely say yes to granting access of bases to the United States.

The second question is whether Japan will use its own forces and assets to defend Taiwan.

Here, I think there are two premises that we have to keep in mind that are different from the US thinking about defending Taiwan. First, there is no legal structure for the Japanese to defend Taiwan when Japan’s security is not involved. There is no mutual security treaty with Taiwan or the Taiwan Relations Act that requires Japan to help Taiwan defend itself.

Second, Japan’s unique peace constitution still restricts the use of force when allies and partners get attacked, while Japan itself is not, and Japan’s security is not involved. There are still conditions that limit the exercise of the right to collective self-defense, even after the Abe government loosened the restrictions in 2014 and 2015. So those are the sort of premises that we have to keep in mind when thinking about Japan’s approach to a Taiwan contingency.

But if China decided that it was necessary to attack US bases in Japan during a Taiwan contingency, that kind of would change the whole game in that the Japanese homeland is now attacked by a foreign government. In that case, I just don’t see any reason for Japan not to act, or I think it’s totally plausible that the Japanese would react and join an operation around Taiwan in Taiwan’s defense. Whether the Japanese are going to send self-defense forces onto Taiwan island, that’s a different level of cooperation. But if Japan were to mobilize its missile defense systems around Taiwan or send navy assets around Taiwan, that’s very possible. Especially now the Japanese are building missile sites in the island chain that connects to Okinawa mainland, in Amami Oshima, Miyako Island, and Ishigaki Island. Yonaguni Island is located less than 70 miles away from Taiwan, about 100 kilometers from Taiwan and now has a radar system. These defense assets are primarily built for the defense of the Southern Western Islands in the East China Sea, but the Japanese defense [annual white] paper is not shy about discussing how close these islands are to Taiwan. The Japanese defense planners must be thinking that they at least have to prepare for the situation in the Taiwan Strait. The question of whether they can do it effectively is another question, but I think that’s the direction the Japanese are going at this moment.

One of my other interview subjects, Dr. Oriana Skylar Mastro, told me that Japanese government officials had told her that attacks on US bases in Japan would not necessarily constitute an attack on Japan in a way that would allow them to exercise self-defense. What are your thoughts on that?

If U.S. bases in Japan are attacked, it is hard to imagine a situation where the Japanese don’t consider that an attack on their homeland and engage in measures for self-defense. Under the constitution, use of force to the minimum extent necessary is permitted for self-defense, when an armed attack against Japan or Japan’s close foreign partners threatens “Japan's survival and poses a clear danger to fundamentally overturn people's right to life, liberty and pursuit of happiness, and when there is no other appropriate means available to repel the attack and ensure Japan's survival and protect its people.”

Let’s say U.S. bases in Japan are attacked by long-range missiles from the Chinese mainland. Would the attacks be so precise and limited that no Japanese civilians on the base and in the neighborhood would be impacted? Would Japanese self-defense force units and assets, which on some bases are co-located with U.S. military assets, be completely saved from the attacks? Even if Japan were to provide only rear support to the United States, wouldn’t the Chinese be interested in attacking those logistical lines connecting to ports, hospitals, or other sites that help run U.S. operations? It is hard to imagine a case in which the Chinese would be able to limit their strikes so much that the Japanese government would simply say that the situation didn’t affect Japanese people’s right to life, liberty, and pursuit of happiness and therefore would not call for measures for self-defense.

I saw that in their latest annual budget request, Japan’s Ministry of Defense included some language about mass producing ground-launched cruise missiles and developing hypersonic warheads. Reuters characterized this as pertaining to longer-range missiles that are able to strike China. Does this mark a departure from Japan’s past restraint in its military development? What sort of constraints do you think Japan is still going to have militarily that other countries like the United States don’t have, and what constraints does it seem to be leaving behind right now?

I think that the government is moving forward with the acquisition of longer-range strike capabilities, but I think the problem unique to Japan continues to be the question of how to operate those. Japan still has its doctrine of an exclusively defense-oriented posture. The current LDP position on using those longer-range missiles is that Japan still maintains this posture by calling these capabilities “retaliatory strike capabilities,” which implies that the Japanese may have to wait until the enemy strikes us first, and then they can retaliate. But I don’t know how the exclusively defense-oriented posture will hold in a realistic sense. There’s also a position taken by the Japanese government that the peace constitution does not require the Japanese to “sit and wait for death.” So while Japan is moving forward with the acquisition of these extended strike capabilities, the question of a preemptive strike while keeping the exclusively defense-oriented posture is going to be a tricky issue, and the Japanese have to debate that going forward.

How ironclad are these legal and constitutional restrictions on the use of force? Do these restrictions present real barriers to the Japanese government doing things that nations with ordinary militaries can do? How high are those barriers?

Legal and constitutional restrictions are the basis on which Japanese defense planners and self-defense forces operate. And I think they do pose high barriers when Japanese defense forces operate with other militaries to exercise and plan for contingencies together. In peacetime, problems with these legal structures may not be as salient as when they are in wartime, and Japanese defense forces cannot plan, exercise, or acquire weapons that go beyond what the law allows. But, as I just said, when an actual crisis comes, these restrictions might not be too ironclad, especially if the government at the time decides that these operational procedures hamper their ability to protect the lives and territories of Japan.

In view of this accelerating military development, the very close alliance relationship with the United States, growing tensions with China, and growing awareness of the Taiwan issue, do you think that any changes to these laws are likely in the foreseeable future? Abe used to talk about amending the constitution; do you see that as something that is possible in the foreseeable future?

The ruling coalition and some other political parties that support constitutional revision already have a ⅔ majority in both houses, so they do already clear the requirement for proposing revision of the constitution, which would then be left to referendums. But that hasn't been triggered yet. If that happens, Article 9 of the peace constitution might also be affected, but I don’t know to what extent they are going to revise the constitution in a way that affects military planning and whether that revision of the constitution would actually help the Japanese government get rid of the exclusive defense-oriented posture. I think people do, in principle, still support a defensively-oriented peace attitude. But I think at this point, the Japanese defense planners or those who care about national security are in agreement that they can’t really wait until constitutional revision to act, because adversaries are already strengthening themselves and the Japanese really cannot waste any more time on military planning. So I think the Japanese are doing what they can within their legal restraints to plan and exercise and increase defense cooperation with like-minded countries including the United States.

Can you explain what the legal or constitutional restrictions are on military spending, how solid they are, and whether they could change at some point?

The Japanese cap on military spending is not a legal constraint—it was just a cabinet decision in the 1970s. Japan traditionally put a cap on defense spending of 1% of GDP in the 1970s, when the Japanese economy was growing rapidly. So even if you say 1%, because GDP was growing so rapidly, there were concerns that defense spending was growing too much without any restraint, and there was a strong socialist presence in Japanese domestic politics that was against unlimited defense spending. So the 1% cap has been there for a while, but it has never been a set-in-stone constraint. In fact, there were other cabinets like the Nakasone cabinet in the 1980s who said they were not going to stand by 1%, but just keep the spirit of the 1% cap on defense spending. And the 2021 defense plan has already surpassed 1% slightly, so there’s no legal cap on this question. It’s a question of how much the Japanese really want to spend on it.

Now, the LDP has already proposed that the government should raise defense spending to 2% of the GDP, but that also means that Japan is going to double the amount of money on defense when it has a rapidly aging society and spending on social welfare continues to rise. So I think there is a consensus in Japan that they do have to increase defense spending, but when it actually comes to battles over the budget, can the ministry of defense double the amount of money it receives all of a sudden? That seems unlikely. This battle over allocation of budget exists in Japan like any other democratic country.

Do Prime Minister Fumio Kishida’s current political woes mean that the LDP could leave power, and if so, could that alter the trajectory of Japan’s defense spending or Japan’s alliance with the United States?

If you look at the domestic political landscape of Japan, opposition parties are still very weak and divided. There are about 10 or more parties, and there isn’t much successful attempt among those smaller parties to build a coalition. Before the DPJ replaced the LDP back in 2009, the DPJ built multiple parties together to defeat the LDP. There’s no momentum like that currently in other parties. Some opposition parties are also in line with the LDP’s foreign policy on constitutional revision or defense spending.

One of the strengths of the LDP is that it’s a big party with different factions with diverse views, so even if the Kishida cabinet falls, there will be a cleansing mechanism within the party to have another group of leaders replace Kishida or have better governance to respond to public opinion.

So I would say first of all, it’s very unlikely that LDP will be replaced, but also even if they are replaced by any other parties, as we saw in the past, that wouldn’t necessarily mean that the foreign policy direction would change.

How would you describe the state of Japan-China relations right now?

I would call the China-Japan relationship a stably chilled relationship. It’s stable and at a low state, but these two countries now seem to have fully come to terms with the fact that they have irreconcilable disagreements on some fundamental national security issues and interests. Japan has had this chilled relationship with China since 2008, I would say, when the Chinese first sent a government vessel into the territorial waters of the disputed Senkaku Islands, so it has already been 14 years. After 14 years, there’s less emotionally-charged domestic debates or domestic divisions in Japan about the threat posed by China, and now the Japanese are ready to think about the next realistic step in policies toward China with cooler heads. China will not go away anytime soon and only get stronger militarily. The two countries have to find a way to coexist in the same region, or else, another war with each other will be catastrophic.

This year marks the 50th anniversary of the 1972 Japan-China joint communique and the start of the diplomatic normalization process. Usually, such anniversary years present a political opportunity to bring forward some of the positive elements of the relationship. This 50th anniversary should have been a big year for that, but what’s interesting is that similarly to 2018, when we had the 40th anniversary of the actual diplomatic treaty, there is no political momentum about using these events as an opportunity to strengthen friendship between China and Japan. That’s how chilled the relationship is. But I’m optimistic that because the two countries have been at that stage for so long, perhaps they can finally start a dialogue on a very calm level.

I interviewed various diplomats who worked on the China-Japan relationship in the 1980s, 1990s, and even 2000s. Those diplomats worked tirelessly for friendship between these two countries, because honestly China’s a very important neighbor for Japan. It really matters for Japan that we have a stable, win-win relationship with China. But if I interview them today, many of them just basically say, China has changed. Back then, some diplomats or politicians could have advocated for Sino-Japanese friendship, even if there was backlash domestically, because there were also people on the Chinese side who would share similar interests in improving ties with Japan and improve the relationship on some level. But now China’s internal politics and foreign policy have changed. Japan and China have also lost their ties over development aid. The Japanese no longer provide aid to China, so those stakeholders are also gone on both sides, and there’s less and less incentive for Beijing to forge friendly ties with Japan as well. My impression is that even among former advocates of the good relationship between Japan and China, the consensus is that China today is a different China.

I might have thought there would be business stakeholders in Japan who are more pro-China, but it sounds like that’s not really a powerful political force.

I would say that the business sector is still the strongest proponent of stable ties with the Chinese. China is still the biggest trading partner for Japan, and for China, Japan is the second biggest trading partner after the United States, so the business sector is still sort of the binding force between the two countries. However, I think a lot of companies are starting to look at the strategic risks of investing in the Chinese economy as well, and the Japanese government is moving forward with diversification to protect key supply chains and aiding Japanese firms relocate back to the homeland in Japan, and then bringing the Taiwanese TSMC to open offices in the Japanese homeland. I believe that Japanese business will continue to operate in China and remain the big advocate for a stable Japan-China relationship on one hand, while on the other hand, some of the key sectors will be decoupled from the Chinese economy.

How does Japan regard the Quad and initiatives like AUKUS? Is it looking to multilateralize security in the Indo-Pacific?

Japan’s not only interested in multilateralizing security architecture in the Indo-Pacific, but I would say that Japan is a key architect behind these initiatives and most active in deepening ties among the “spokes” of the U.S. alliance system in Asia, often described as the hub and spokes system. Japan has deepened its own defense security partnership with Australia for almost two decades now, and with India of course, and the UK, NATO, Canada, and ASEAN countries as well. Japan is a key proponent and also arguably the originator of the Quad framework, and it is also keenly watching the development of AUKUS. There are multiple working groups under AUKUS, but there are discussions in Japan that there may be ways for Japan to be involved in some of the working groups under AUKUS, such as studies of cybersecurity, AI, and quantum technologies. Those are going to be very important topics for Japan to be cooperating with like-minded countries, so I can see Japan being interested and potentially joining, if possible, the AUKUS framework.

One of the reasons why Japan’s so interested in deepening ties of the US-led alliance security architecture in Asia is to make sure the US stays engaged in the region. It’s one of the binding mechanisms vis-à-vis the United States through multilateralizing and deepening ties among U.S. allies. The second way to look at it is also hedging. If US foreign policy is uncertain and more unpredictable, Japan doesn’t have any other good option but to strengthen ties with other like-minded countries. Japan still has to find a way to expand and balance against China or North Korea, and of course Russia, and the relationship with South Korea is not always easy, so some of the countries that wouldn’t have these difficulties of historical memory, like Australia, India, or Canada, NATO countries, are valuable partners for Japan.

In terms of Japan’s relationship with Taiwan, is it upgrading that relationship in any specific ways?

I don’t see any key changes on the official level, but there is certainly growing interest among parliamentary members to visit Taiwan. Parliamentary exchanges are going to continue to serve as vital fora that connect the key people in both countries who would then impact policymaking. Just a couple months ago, when Nancy Pelosi was about to visit Taiwan, a group of bipartisan parliamentary members who were former defense ministers also went to Taiwan. Those high-level visits are going to be a more salient way of strengthening ties with Taiwan. Once they are in government and have official positions, however, legal constraints or the difficulties of not having diplomatic ties will still come into play.

Where do you see US-Japan relations going if Donald Trump returns to the presidency, or if Joe Biden is replaced by someone else?

It’s hard to predict how the US-Japan relationship will evolve if Trump were to win another four years. I think that Japan was one of the few countries that managed the relationship with President Trump well, perhaps the best compared to other US allies. But looking at those four years, what Japan showed is that it really doesn’t have any alternatives but to hug any US government and attempt to shape US foreign policy toward achieving Japanese national interests, especially in areas of shared interests between the two countries. So even if a new Trump-like administration comes into power, the Japanese government will still try to connect with whoever [they can] in those administrations to have deeper engagement toward achieving shared interests and to shape US foreign policy as an ally. If the US no longer listens to the Japanese suggestions or takes on policies that harm Japanese national interests, then there might actually be some rethinking about alternatives, but there is not really a good alternative. Japan will continue to deepen its defense ties with other like-minded countries, but I think Japan still wants the US to be the leader of this security architecture in Asia. Without the US actually holding the flag, it’s really hard for other US allies to come together, especially on issues like the defense of Taiwan. So that’s sort of the lesson for the Japanese government, that the Japanese will just do their best in connecting with any government in Washington.


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