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Danger and Deterrence in Japan’s Security Environment

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Danger and Deterrence in Japan’s Security Environment

“We must handle the hypothesis of an imminent threat as long as nuclear weapons exist.”

Danger and Deterrence in Japan’s Security Environment

Military vehicles carrying DF-5B liquid-fuel intercontinental ballistic missiles (ICBM) march in a military parade in Beijing, China, Sep. 3, 2015. China’s military build-up has sparked Japan to change its defense strategy.

Credit: Depositphotos

As Hamada Yasukazu, former minister of defense of Japan, explained in the document “Defense of Japan 2022,” the world is at a moment of historic change: “The international community is facing its greatest challenge since the Second World War.”

For Japan, the regional context could not be more complicated: Russia’s invasion of Ukrainian territory marked a new era of crisis, given that the country is a permanent member of the U.N. Security Council, yet it did not consider international law and even threatened to use nuclear weapons. 

Likewise, China is dramatically increasing its military capabilities both quantitatively and qualitatively, including missiles and nuclear weapons, while continuing to pursue unilateral changes in the status quo in the East China Sea and South China Sea. Additionally, North Korea is rapidly advancing its missile and nuclear weapons development. In addition to destabilizing the Korean Peninsula, Pyongyang has repeatedly launched missiles over Japanese territory in recent years.

To strengthen its defense system, Japan has been making an extraordinary investment, setting itself the goal in December last year of spending 43 trillion yen or $302 billion in the period 2023-2027.

For this reason, Japan has also deepened its military cooperation with the United States, its only ally. Today, there are 120 U.S. military bases on Japanese territory, housing a total of 57,000 U.S. troops, 70 percent of which are in Okinawa.

In this context, ReporteAsia recently had the opportunity to interview Dr. Akiyama Nobumasa, a professor at the School of Public and International Policy and the Faculty of Law of Hitotsubashi University. Akiyama is one of Japan’s leading academics and one of the most prolific in terms of published writings on defense and denuclearization.

Akiyama confirmed that, in the region, China and North Korea are Japan’s two major concerns, particularly because of their rapidly expanding nuclear programs: “Based on estimates, China could have 400 to 500 nuclear warheads and this would increase to 1,500 by 2035,” he said. “…This is a very abundant, dangerous arsenal, which raises concerns for all of us who advocate denuclearization.”

Akiyama noted that China is diversifying its missile arsenal, including long-range missile which it can directly attack the United States. China has also developed medium-range missiles that can carry nuclear warheads to Japan, the Philippines, Guam, and other countries.

Meanwhile, it is worth noting that China is Japan’s largest trading partner and one of the largest investment destinations for Japanese companies. Economic relations between the two countries, including trade and investment, are very close. Total trade between the two countries was $335.4 billion in 2022, up 14.3 percent from 2021, according to figures from the Japanese Ministry of Finance. Likewise, Japan is China’s second-largest trading partner (after the United States), to which it exports key parts for its technological development such as semiconductors, manufacturing equipment, and electronics.

Along with China’s economic growth, the strengthening of its military began to worry its neighbors. “Their tendency to expand their nuclear arsenal, if it only has to do with the threat from the United States as they claim, raises questions: Why then did they develop medium- and short-range missiles that are to attack nearby targets such as Japan?” Akiyama asked. 

“We need more channels of communication between the two countries. If, as they say, the growth of their nuclear arsenal does not create any danger to their neighbors, they have to convince us through their behavior. That is the situation. We are looking for predictability in China’s behavior.”

As things stand, Akiyama said, there is a growing threat perception in Japan from China. To explain the shift, he gave an example: “The Japanese government recently decided to add the U.S.-made Tomahawk missile to its arsenal as a means of counterattack. It is striking that if it had tried to push for this purchase 10 or 15 years ago, it would have come in for a lot of criticism. But now, by contrast, [the government] has gained a lot of public support,” he explained.

“I think today the majority of the population agrees with Japan’s introduction of counter-strike capabilities. The context is the growing threat perception from China: it happens now that the majority of the population shares that same feeling.”

As Akiyama argued, Japan is obliged to prepare to defend itself, because it cannot depend only on the intervention of the United States. “If China considerably increases its nuclear arsenal and the variety of missiles, we face a number of challenges: The first is that in the face of an international conflict… China and the United States [could] enter into a war, which could include nuclear weapons. So that in that case, the United States would not really be able to assist Japan if the war were to spread to Asia.”

Although Akiyama does not believe that in the current context, it makes sense to think that China could use nuclear weapons against Japan, the growth of its arsenal also suggests that it has multiple war aims in its offensive strategy. “In the hypothesis of a large-scale international conflict, given Japan’s alignment with the United States, it would only be feasible that China could use its nuclear weapons in some way against Japanese territory. But I don’t consider it the most logical or the most likely option.”

Likewise, Akiyama believes a nuclear attack from North Korean on Japan would not be logical, and so is unlikely. 

“Nevertheless,” he continued, “their actions are dangerous: They are demonstrating their abilities by launching missiles that cross our territory, which means that they have that capability already well advanced. But their tests are more focused on showing capabilities to attack long-distance targets, such as the United States.”

Still, Akiyama said, we cannot rule out the possibility of North Korea using its nuclear arsenal in a local conflict. “The problem with all this tactical nuclear weaponry at North Korea’s disposal is that, in the event of an escalation of the war scenarios, it is much more likely to use these resources before other conventional resources in which, on the other hand, it does not have such an advantage. This is very dangerous.”

This, in turn, is pushing South Korea to beef up its own military – just as Japan is doing. This stems from a combination of North Korea’s increasing military capabilities and uncertainty about the U.S. security guarantee, Akiyama explained.

“There is much debate about Donald Trump’s attitude if he were to be elected for a second time. In his first term, he expressed serious intentions to withdraw U.S. troops from South Korea. This imposed a strong sense of weakness on South Korea at the geopolitical level,” he said. “Then, the fact that the U.S. may not be a long-term ally for South Korea implies that South Korea should stand up to North Korea on its own, and this also sets up serious threats in the whole region.”

In this context, South Korea’s strategic planning is inextricably connected to Japan’s. “North Korea’s hostile attitude will not stop. Therefore, if South Korea were to need to counter that aggression, it is easy to think that it would seek to align itself more concretely with the United States and Japan,” Akiyama commented. 

“Indeed, in the event of an escalation of regional conflicts, it will be important for the more effective operation of U.S. forces on the Korean Peninsula to use the military bases located in Japan. Therefore, South Korea needs to rely on the Japanese Self-Defense Forces [SDF] for its own protection.”

Japan’s role in helping preserve stability in the Indo-Pacific goes beyond Northeast Asia, Akiyama pointed out. “It is known that it was Prime Minister Shinzo Abe who introduced the Free and Open Indo-Pacific concept in 2016, which shows Japan’s interest in the stability of the region.”

Japan is not pursuing these efforts alone. “I believe that there today Japan has a reliable partner in Australia, which is also concerned that the region does not come under undue pressure from China,” he explained. “Both countries are discussing possible military cooperation in the event of simultaneous contingencies in their respective regions of influence. This will increase the sophistication and frequency of joint exercises between the SDF and the Australian military. This activity is in response to the Australia-Japan Joint Declaration on Security Cooperation signed by Prime Ministers Kishida Fumio and Anthony Albanese in October 2022.”

Japan is also rapidly developing close security ties with the Philippines, which has seen a serious flare-up in maritime disputes with China in the South China Sea. “Therefore, in the Philippines the negative perception of China is growing,” Akiyama said, “and also because of this the authorities of that country are seeking more contact with the United States, to counteract the influence of Beijing in that area.”

“I could also say a lot about our relationship with India, which is very good,” he continued. “From a geopolitical perspective, I must also explain that we do not use this relationship as a tool against China: It is based on the fact that we share universal values and a thriving economic relationship.”

Even while pursuing more robust self-defense capabilities and security partnerships, however, Japan’s government has been increasing efforts toward the world’s denuclearization. In 2022, when Japan was the host of the G-7 summit, Prime Minister Kishida seized the opportunity to put forward the Hiroshima Action Plan, which received acknowledgement in the G-7 Leaders’ Hiroshima Vision on Nuclear Disarmament.

As Akiyama explained, “This plan set out five pillars for advancing denuclearization: continuing not to use nuclear weapons; improving the transparency of nuclear capabilities; maintaining the downward trend of the global nuclear arsenal; ensuring nuclear nonproliferation and promoting the peaceful use of nuclear energy; and encouraging international leaders and others to visit Hiroshima and Nagasaki.” 

The move was “well-timed,” Akiyama argued, “because it came just as Russia reminded us of the [possibility] of nuclear weapons [use]… I think [the Hiroshima Action Plan] was courageous for the cause.” 

However, he acknowledged that “there was no major breakthrough for denuclearization advocates. Because we have to face a reality: We have to manage the hypothetical of an imminent nuclear threat as long as nuclear weapons exist. 

“China is expanding in nuclear weapons, and North Korea is following, can we close our eyes?”

For Akiyama, the answer to this puzzle is not to pursue nuclear weapons but to ensure deterrence while pursuing diplomacy. “In Japan, we have to show – not at the nuclear level, but at the conventional level – that we are prepared to handle their threats and that no country is prepared to achieve its objectives by the use of force. We have to convince them that only diplomacy and international relations are the way to achieve geopolitical objectives.”

Seen in this light, Japan’s defense relationships are also a crucial part of its deterrence. “If China sees an increasingly strong U.S. relationship with Japan and they envision this trend expanding to South Korea, the Philippines, Australia, and Malaysia – if this happens it would change the environment for strategic dialogue with Japan,” Akiyama concluded. “Even better if the role of nuclear weapons diminishes and ceases to be a space of threat.”

A longer version of this interview was first published in Spanish by Reporte Asia. This translation is published with permission.