Roundtable Discussion—Let's Talk Frankly About Nuclear Issues
The 59th SSDP Discussion Session
May 24, 2023

Moderator: Nobukatsu Kanehara
Participants: SSDP members

Nobukatsu Kanehara: I would like to ask for opening remarks from Mr. Kato and Professor Kamiya.

Yoichi Kato: Allow me to make four comments. First, what roadmap will the G7 Leaders' Hiroshima Vision on Nuclear Disarmament follow? How should nuclear disarmament be pursued while maintaining and strengthening nuclear deterrence? Looking at recent nuclear debates in the United States, it seems that the prevailing tone is not to reduce the roles and number of nuclear weapons but to increase the number of deployable nuclear weapons. If the United States is, for the time being, aiming for a two-front nuclear parity with China and Russia, the next step to take would be to reinforce its nuclear arsenal. How could the United States transition to reducing nuclear weapons after achieving parity? That is the big challenge. Neither China nor Russia has shown any interest in nuclear disarmament.

Second, I think China's nuclear threat could be a nuclear detonation for demonstration purposes rather than a counterforce or counter-value attack. If targeting Japan, China would detonate nuclear missiles in, for example, the waters of the western Pacific Ocean to the east of the Nansei Islands. During a conference organized by the Defense Threat Reduction Agency (DTRA), an offshoot of the Pentagon, a former Pentagon official once stated that a demonstration nuclear detonation would not be deterred by the US nuclear strategy. He explained that should such a "nuclear attack" occur, the United States would not consider it a failure of nuclear deterrence. However, if, in a Taiwan contingency, a nuclear missile were fired into the waters near Japan, causing a nuclear explosion, there would take place a disturbance in Japan, even if suffering no casualties. Moreover, if the US government took the position that it would not regard it as a failure of nuclear deterrence or take retaliatory action, the credibility of US extended deterrence and the Japan-US alliance as such would inevitably be undermined. A grave situation may occur. The United States should revise the interpretation that nuclear attacks (explosions) for demonstration purposes should not be dealt with by US nuclear deterrence.

Third is a question of whether the United States would carry out nuclear retaliation if a country enjoying US extended deterrence is nuked. At the DTRA-sponsored conference mentioned above, the US representative said that the United States does not decide in advance whether or not to use nuclear weapons in retaliation for a hostile nuclear attack. He mentioned that with the US forces' high targeting and precision guidance capabilities, nuclear warheads are not necessarily indispensable to destroy an enemy's nuclear missiles before launching; conventional weapons would be sufficiently effective. However, the "Washington Declaration" recently agreed to by the United States and South Korea as a new countermeasure against North Korea's accelerated nuclear and missile development provides for the calling at South Korean ports by US strategic missile submarines (SSBNs) and presupposes nuclear retaliation against a hostile nuclear attack. Many Japanese citizens must believe that such is the US "extended deterrence." We should reconsider the possibility of retaliating against a nuclear attack with conventional forces, not only from the viewpoint of military rationality but also from the viewpoint of the possible impact on Japanese public opinion.

Fourth, a nuclear attack on Taiwan. Just recently (May 22), the Legislative Yuan of Taiwan discussed the potential of Taiwan being placed under the nuclear protection of the United States. The topic attracted wide attention when Foreign Minister Joseph Wu stated, "We had been in communication with ‘good friends (the United States)' regarding this matter." According to a former Taiwanese government official, no definite actions have thus far been taken. But the fact that such discussions are taking place in the Taiwanese parliament indicates that the threat of a Chinese nuclear attack is taken seriously by Taiwanese citizens. Military experts have been paying more attention to the high-altitude electromagnetic pulse (HEMP) attack, or detonating a nuclear weapon in space, rather than a direct nuclear strike. Reportedly, China regards the HEMP attack as the most powerful means of electronic warfare. They assert that it is different from a nuclear attack and, consequently, it does not constitute the preemptive use of nuclear weapons. The HEMP attack is also considered a potential means to neutralize the US carrier strike group. I believe the HEMP attack should be regarded as a nuclear attack and be subject to US nuclear deterrence. If the HEMP attack were launched against Taiwan, Japan would also suffer. Can it be classified as an "armed attack situation" for Japan or not?

Matake Kamiya: First, I would like to talk about reality and ideals. Japanese people, including myself, dislike nuclear weapons, and therefore, we tend to wince when encountering words such as a nuclear-free world. The late Masataka Kosaka said that realism without ideals corrupts, but on the other hand, idealism without staring at reality also does. A nuclear-free world is an ideal that we can all agree on, but I cannot believe that it is currently a practical or urgent objective. As experts, should we not inform the public that this is not the case? It is undeniable that the possibility of using nuclear weapons is increasing, given Russia's nuclear threats and North Korea's development of nuclear weapons and missiles. I think that the most pressing issue at this moment is not so much the elimination of nuclear weapons as the prevention of their use. We should consider what is necessary to prevent the use of nuclear weapons; to that end, we must now focus on nuclear deterrence and non-proliferation rather than nuclear ban and abolition.

In this connection, I would like to say that to prevent further nuclear proliferation in Northeast Asia, Japan's nuclear policy (non-nuclear policy) should be "adaptable" rather than "fixed." The reason why North Korea is developing nuclear weapons and missiles as it is and China is promoting vertical proliferation (buildup) of nuclear weapons may be, at least, partly explained by the fact that Japan has repeated that it will never possess nuclear weapons, no matter what any other country does. I believe Japan should have done something, rather than nothing, in response to such moves by the neighboring countries. I have consistently opposed Japan's nuclear armament. But if Japan only maintains its non-nuclear policy without taking any action, other countries may wrongly assume that they can engage in nuclear activities without considering Japan's response. If we could have no choice but to possess nuclear weapons, we should consider the possibility. In South Korea, voices are calling for nuclear armament; if South Korea were to acquire nuclear weapons, Japan might no longer have the option of not possessing them because all Northeast Asian countries but Mongolia would become nuclear states. This raises the question of whether Japan could remain the only non-nuclear state in the region. To prevent nuclear proliferation, Japan must seriously address the nuclear issues.

Nobukatu Kanehara: The issue of what nuclear parity between China and Russia versus the United States would look like is of great importance. I remember a nuclear meeting presided over by former US Secretary of Defense Chuck Hagel and former British Foreign and Defense Secretary Malcolm Rifkind at the Chicago Council on Foreign Relations, where there was serious discussion about the importance of self-help efforts within Europe in the future and the possibility of extending the British and French nuclear umbrella to Germany. It may be their thinking that the West, as a whole, should pursue parity with China and Russia, allowing for the nuclear weapons of the United Kingdom and France.

The issue mentioned by Mr. Kato of using small nukes for demonstration purposes or in EMP attacks is a side-line argument in the realm of nuclear deterrence. Whereas it is an important topic, it does not logically follow that attacks using small nuclear weapons must be retaliated against by small nukes. It suffices for a nuclear state to have nuclear deterrence work as a whole by combining conventional and nuclear forces; even if deterrence fails and small nuclear weapons are used against its ally, the nuclear state prioritizes winning a conflict at any expense. Yet, it remains to answer how to deal with the sentiment of vengeance harbored by the nation attacked with small nukes or their fear of being attacked again with the same. Isn't it natural for non-nuclear allies to feel uneasy in that way? However, these kinds of question may be understood as related to reassurance for those non-nuclear allies, not nuclear deterrence as such. I think the debate concerns how to reassure or convince those allies. Nuclear weapons are ultimately no more than weapons; people employ them to win. If they are not necessary to win, people will not use them to avoid futile escalation. This is the way nuclear powers think.

Firing a nuclear missile into the ocean does not mean it is less harmful because no humans inhabit there. Depending on areas, resulting ocean pollution may have a significant impact on fishing, tourism, and shipping. The American TV drama "24" depicted a story of terrorists, who, at wit's end about how to stop a nuclear bomb from exploding, wondered whether to detonate it at sea or on land and finally decided to explode it in the Nevada desert because it would cause less damage.

Armed attack situations will not be declared in the wake of a single incident that, for example, happens in Japan's territorial waters. In cooperation with the United States, Japan will gather information on enemy forces from cyberspace, outer space, and all other sources available and make a comprehensive judgment based on those pieces of information. If the situation involved the enemy's use of nuclear weapons for demonstration purposes or in EMP attacks, additional various information on the movements of enemy forces would flow in, and a judgment regarding armed attack situations would be made promptly.

Narushige Michishita: First, options such as detonating nuclear weapons in the air for coercive purposes would not work too well. Imagine a situation in which a country uses nuclear weapons for demonstration purposes but the opponent does not budge. If the former fails to further escalate the situation, the latter will realize that the former is not serious about using nuclear weapons, undermining the credibility of its coercion. Consequently, once a country employs nuclear weapons for demonstration purposes, it will eventually be forced to use them against real targets. In any case, we need to find ways to deter and, if deterrence fails, deal with coercive nuclear use.

Second, civil defense measures such as the J-Alert early warning system are important. What is called "civil protection (kokumin hogo)" in Japanese is actually civil defense. Civil defense measures are critical in two ways. For one, it would reduce casualties in war. Early evacuation and relatively simple protective actions would reduce the human toll significantly. For another, civil defense exercises would make Japanese citizens better prepared psychologically. Those who know what to do to protect themselves in crises or wars are less likely to panic than those who do not. In modern hybrid warfare, psychology can matter as much as physical battles.

Third, when retaliating against a nuclear attack with conventional forces, attacking the adversary's nuclear arsenal can be a useful option. For example, threatening the enemy's nuclear-powered ballistic missile submarines (SSBNs) with conventional forces is an interesting option. In fact, this "anti-SSBN strategy" constituted an important part of US strategy during the Cold War.

Finally, an electromagnetic pulse (EMP) attack might not be so useful. Given its untested nature, it is uncertain what kind of damage it would create. That uncertainty seriously limits the utility of EMP as a credible weapon.

Nobushige Takamizawa: There are various opinions about the Hiroshima Vision. As the National Security Strategy and the National Defense Program Guidelines have clearly stated that Japan's ultimate security goals consist in the enhancement of deterrence and the abolition of nuclear weapons, I believe there is no contradiction at all between these two policy lines. On the other hand, the curtailment of the role of US nuclear weapons has not become clarified. Yet, as the deterrence structure dependent on nuclear weapons changes, responses using, among other measures, conventional weapons attract emphasis; it may be possible to pursue the curtailment of the role of nuclear weapons in this context.

To increase public awareness, we can study how European countries responded during the Cold War in terms of psychological defense or total defense.

Regarding the use of nuclear weapons for demonstration purposes, we need to consider, rather than its probability, what specific forms it might take and what preventive measures could be taken.

In any case, since Japanese public sentiment favors nuclear abolition, it is vital to consider what kind of theory can develop from the standpoint of the Japanese anti-nuclear mindset.

Masahiro Akiyama: In the Ukrainian war, Russia failed to assess Ukraine's military power and, as a result, could not deter Ukraine. When Ukraine became independent years ago, it gave up its nuclear weapons. If the country had retained them, it would not have received nuclear threats from Russia this time. On the other hand, one could say that North Korea has developed so many nuclear missiles for such a small country. It is now difficult for the United States to attack North Korea as it has deterrence. Although the United States is supporting Taiwan, since Taiwan is not a US ally, it appears that Taiwan is determined to defend itself against any potential attack from China. The United States is now helping Taiwan's military buildup. In this connection, debates are underway in Taiwan, such as whether Taiwan should have some form of nuclear capability (nuclear sharing is another option) or a deterrent force capable of implementing effective counterattacks or missile strikes in response to China's nuclear strike. Can Taiwan acquire such a deterrent force?

Nobukatu Kanehara: In terms of total firepower and total military power, Taiwan cannot confront China single-handedly. No matter what it attempts, the result will be futile. Even if it fired a missile at Shanghai, it would be paid back double. The weaker side cannot deter the stronger side. Only with the support of the United States could China be deterred.

Yoichi Kato: Taiwan attempted to develop nuclear weapons in the past. In response to China's successful nuclear test in 1964, President Chiang Kai-shek secretly initiated an atomic bomb project in the late 1960s. There were various developments before and following the diplomatic break with the United States in 1979. But the project was finally abandoned in 1988, shortly after President Lee Teng-hui took office, due to pressure from the United States. However, the United States does not extend a "nuclear umbrella" to Taiwan. This is because, following the so-called "strategic ambiguity," the United States does not declare that it will directly defend Taiwan. The prevailing belief in Taiwan's media and public opinion is that China is unlikely to initiate a nuclear attack on Taiwan. But as the above discussions in the Legislative Yuan indicate, the need for a "nuclear umbrella" is beginning to be discussed in the political arena with China's increasingly aggressive stance as background. If the US-China confrontation over Taiwan escalates to the stage of an exchange of nuclear attacks, will the United States go to great lengths to protect Taiwan at the risk of exposing its own territory and citizens to nuclear attack? This is a subtle question hard to judge. The judgment may differ depending on the US administration of the time. If the situation escalates to such a point, Japan will also face the question of whether it should support Taiwan.

Nobukatu Kanehara: How would the United States react to a Taiwan contingency? The US State Department is continuing its "ambiguity strategy" of keeping its attitude ambiguous, but the overall mood in the United States favors the defense of Taiwan. The reason for this is that Congress is steaming. In the past, Republican conservatives who disliked the Communist Party supported Taiwan, but now the human rights Democratic left is supporting Taiwan. According to Mr. Kato, President Lee Teng-hui gave up developing nuclear weapons. President Lee thought that Taiwan needed to secure the commitment of the United States to its survival and that the only way to involve the United States was to democratize Taiwan. I think he was a genius. The United States cannot so readily abandon Taiwan, which has become an island of freedom. What I fear most is that the United States attempts to deal with a Taiwan contingency half-mindedly. In this case, even if the United States ultimately wins, Japan and Taiwan, the front-line states, will be severely damaged. Instead, I hope the United States quickly declares that it will "protect Taiwan (but will not recognize its independence)" and extend the US nuclear umbrella to Taiwan while initiating a nuclear arms control and disarmament process with China, thereby realizing cold peace in the Taiwan Strait.

Matake Kamiya: The reason why North Korea has deterrence, whereas Taiwan does not, is that Taiwan does not possess nuclear weapons for now, but that is not all. The target countries of their deterrence are different in the national character. Even if Taiwan could acquire a small number of nuclear weapons, it is doubtful that it could deter China with them. Meanwhile, North Korea is quarreling with the United States and South Korea. If it goes to war, undoubtedly, it will lose, but it may inflict some damage on the opponents in a last-ditch, desperate attack. That is what makes "law-abiding" countries fearful. I am not sure if China thinks the same way. If confident to win, China may be willing to make considerable sacrifices. Nobody knows a nuclear Taiwan can deter China.

Yoichi Kato: What roadmap will the Hiroshima Vision follow? The United States may not attempt to establish full parity with China and Russia but choose to increase its nuclear warheads by 1,000 or 2,000 over the current level. Such discussions in favor of nuclear expansion are underway in the United States. If that happened, what would become of the Hiroshima Vision?

Nobushige Takamizawa: The question of the number of nuclear weapons is challenging. The National Security Strategy of Japan states with China in mind that Japan will halt and reverse "the trend of arms buildup, including nuclear weapons, in the vicinity of Japan," and the G7 Leaders' Hiroshima Vision on Nuclear Disarmament states, "The overall decline in global nuclear arsenals achieved since the end of the Cold War must continue and not be reversed."

It appears that there is no viable solution that can address the complex issue of nuclear parity between China and Russia versus the United States, given these premises. One logical way, whether appropriate or not, is to weaken Russia. Another solution would be the combined use of conventional forces and the status-quo number of nuclear weapons following the policy of integrated deterrence. There is also the question of how the United States can stage a direct bilateral dialogue with China refusing multilateral talks. It depends on how the United States can package as many important topics as possible besides nuclear parity.

For Japan to sum up that the Hiroshima Summit has successfully contributed to nuclear disarmament, the key will be how to develop the Hiroshima Vision shortly. I think it vital for Japan to take the lead in transparent discussions on the nuclear strategy doctrine involving China and Russia and to link this move to the issue of China's nuclear buildup. It may be hard to score concrete progress on the specific issues raised in the Hiroshima Vision. Meanwhile, a working group will be formed to improve the NPT review process that will begin this year; I look forward to this group's discussions.

Masahiro Akiyama: What is the mechanism of and discussions about US nuclear deterrence regarding Taiwan? Is the United States seriously thinking of nuclear deterrence against China or not? Is the nuclear deterrence debate in the US security community functioning well under the Biden administration? What would the debate look like under a Trump administration?

Masashi Murano: It is known also in Japan that in the past year or two, the security community in Washington has been increasingly focusing attention on a Taiwan contingency. Some in the nuclear community have likewise begun to discuss scenarios for using nuclear weapons in a Taiwan contingency. They are discussing scenarios in which the United States uses nuclear weapons first in addition to scenarios in which the Chinese side uses nuclear weapons first. They are also assessing the effect of launching nuclear attacks on, for example, China's maritime transport, landing forces, or ground camps. The consensus of these discussions was that the United States should never employ nuclear weapons first for demonstration purposes. As for China's first use of nukes, the US nuclear community's assessment is similar to what Dr. Michishita has discussed; they are discussing how the United States should address such a case. Theirs is a discussion from a broader perspective, focused on how to deal with China's use of nuclear weapons in a Taiwan contingency, rather than whether to extend the nuclear umbrella to Taiwan. Their discussion is not narrowed down to whether or not the United States should use nuclear weapons in the event of China's nuclear attack on Taiwan. It is undeniable that the Biden administration, even if China employed nuclear weapons, is inclined to avoid nuclear escalation without using nukes if possible. The Nuclear Posture Review (NPR) issued last year is similar in wording to the Obama administration's 2010 NPR. Few people in the Biden administration call for the active use of nuclear weapons. Even if Russia used nuclear weapons in Ukraine, the current US administration would respond with conventional forces if at all possible. That said, it is unforeseeable how a Republican administration, especially a Trump administration again, would respond. The Republican camp boasts a wide array of nuclear experts, and the Trump administration's 2018 NPR was a well-written document. Yet, since the use of nuclear weapons is the President's prerogative, it may be that if Trump becomes president, he may not want to use nuclear weapons based on different reasoning from Biden. The G7 Summit set out nuclear disarmament goals based on the Hiroshima Action Plan proposed by Prime Minister Kishida. How should such a Japan ask the United States to expand its nuclear arsenal, now at the threshold of the era of the tripolar nuclear system? I have a question regarding whether the current nuclear posture at the New START level can provide enough assurance for Japan's expanded deterrence needs, especially as the world enters the era of the tripolar nuclear system. Even if Japan remains silent, the United States will probably have no choice but to expand its nuclear arsenal in the not-too-distant future. A less politically disruptive option would be to passively support the US decision and acknowledge that it is based on their current mood and circumstances. Instead, we must have a broader discussion and reach some consensus on whether Japan should proactively ask the United States to expand its nuclear arsenal.

Nobukatsu Kanehara: I agree with Mr. Murano's opinion. We Japanese must think about Japan's security. We must have our requests considered by the United States. Alliances between nuclear states and non-nuclear states are not free from the question of mutual credibility. As was the case of West Germany in the past, a non-nuclear ally on the front lines is subjected to a "sacrificial pawn" psychology. Looking back to the past security policy debate in the Japanese Diet, it was only part of the regime debate under the 1955 system, and the leftists' nuclear debate was devoted to weakening the US nuclear deterrent and damaging its credibility. Although nuclear issues are related to Japan's most critical security interests, no substantive debate has been undertaken by the government or the Diet. The Japanese government and Diet have failed to fulfill their responsibility regarding nuclear issues. From now on, Japan must hold prime ministerial talks with the United States to discuss nuclear strategy, too.

Narushige Michishita: It is not enough to simply ask the United States to increase the number of nuclear weapons. The number alone does not produce credible extended deterrence. Japan and the United States have to discuss nuclear weapons' deployment, delivery systems, targeting, and operations. Also, they must take a close look at the nuclear decision-making process and consider ways to enhance the credibility of extended nuclear deterrence.

Shinzo Yoshida: Is there no concerns that whereas the United States articulates its willingness to provide extended deterrence to its allies, its key partners, for example, Japan, will wince at the last minute? Imagine that China detonates a nuke just for intimidation with no intention to attack Japan. That alone would likely cause a disturbance in Japan, leading to calls for "staying away from America." The cabinet might fall. The United States would be placed in an awkward situation of finding the ladder gone after climbing a tree. Even if the United States were to defend Taiwan with all its might involving its allies, isn't there a likelihood of facing opposition from its foremost ally? How should we assess the vulnerability inherent in the theory of extended deterrence?

Matake Kamiya: Nuclear cuts should not be an absolute goal. The realistic and urgent goal is to prevent nuclear use. To this end, deterrence is necessary, and it is likewise crucial to discuss the current state of the US nuclear arsenal, including whether the current level is sufficient or not for deterrence. The US and Japanese governments should increase opportunities for necessary consultation.

(Translation by Tsutomu Inuzuka)

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