The independent resource on global security

Japan’s new military policies: Origins and implications

Japanese military base, Japan Self-Defense Forces. Photo: Shutterstock
Japanese military base, Japan Self-Defense Forces. Photo: Shutterstock

Japan is undergoing the most significant changes to its security strategy since the end of World War II. In late 2022, Prime Minister Fumio Kishida’s government approved three policy documents—the National Security Strategy (NSS), the National Defense Strategy and the Defense Buildup Program—that propose a significant expansion of Japan’s military capabilities and a major increase in military spending over five years. The documents enable important modifications of the senshu boei (exclusively defence-oriented policy) that Japan has followed since 1946, not least allowing Japan to participate far more actively in collective self-defence with the United States and to substantially increase its ability to project force beyond its borders.

What factors have influenced these changes, what do they mean for security in the Indo-Pacific region, and what challenges lie ahead in their implementation?

Japan’s changing security environment

The new documents ascribe the changes to a deteriorating international and regional security environment, as well as expectations from its longstanding ally the USA and others that Japan should play a role ‘commensurate with its national strength’ in protecting the ‘post-war international order’. The government has been at pains to reassure the Japanese public, and the wider world, that the new policy direction does not alter Japan’s commitment to peace and regional stability.

Japan certainly faces some serious security challenges today. China is rapidly strengthening its military power, including expanding its nuclear arsenal and missile and naval capabilities. Japan is particularly concerned about increasingly frequent Chinese intrusions into the contiguous waters and air space of the contested Senkaku/Diaoyu islands and intensifying military activity in the East China Sea. The new NSS characterizes China as ‘the greatest strategic challenge in ensuring the peace and security of Japan and the peace and stability of the international community’—which China was quick to react to.

Growing tensions between Beijing and Taipei also potentially threaten Japan’s security interests. Any military conflict would turn Japan’s reliance on energy imports and international trade into major liabilities. Indeed, Tokyo has become increasingly vocal about the importance of maintaining peace and stability across the Taiwan Strait.

North Korea’s nuclear and missile developments have also been key factors. Since North Korea’s 1998 Taepodong missile test, Japan has focused on developing and deploying missile defence systems such as Patriot and advanced Aegis missile defence interceptors. With North Korea developing and testing new missile designs and steadily expanding its nuclear arsenal, it is now in a position to strike targets in Japan, including US bases in Okinawa.

Finally, Russia’s invasion of Ukraine deeply shocked Japan, which was among the first countries to condemn Russia’s actions and impose sanctions. Japan and Russia have unresolved disputes over the South Kuril Islands (also referred to in Japan as the Northern Territories). Russia, like China, has in recent years increased its military activities around Japan and its contiguous waters and has deployed missile systems on the Kuril Islands. China and Russia have also conducted joint military exercises, and their combat planes have entered Japan’s air defence identification zone.

How big is the break with the past?

The Kishida government’s announcement that it will increase annual defence spending to two per cent of GDP by 2027 has made headlines. From 1960 to 2020, Japan’s military spending remained at or below one per cent of GDP. However, perhaps the most radical departure from Japan’s earlier security policy is the decision to acquire and deploy new counterstrike capabilities that would greatly increase its ability to target enemy forces far beyond Japan’s borders.

Japan’s defence posture is shaped by Article 9 of its 1946 constitution. Successive governments interpreted this article as mandating the use of armed force only in the case of an armed attack on Japan’s territories and people. As Japan became a major economic power in the 1970s and 1980s, domestic discussions emerged as to whether it should ‘normalize’ its foreign and security policy, including allowing the use of force outside of its own borders to support another country’s defence. However, it was not until 2015 that former prime minister Shinzo Abe pushed through legislation that allowed the Japan Self-Defense Forces to engage in overseas combat missions.

The new strategic documents mark a major step towards this kind of ‘normalization’. However, they must be seen in their broader context of not only Japan’s worsening security environment but also its responses. These responses—addressed below—include a multipronged national security strategy firmly anchored in its alliance with the USA, the need to maintain economic security, and security partnerships with ‘like-minded’ countries.

Japan’s broader security policy

The Japanese–US alliance remains the linchpin of Japan’s national security strategy. In the six decades and more since the signing of the 1960 Treaty of Mutual Cooperation and Security, the alliance has evolved from one where Japan was completely dependent on US protection towards one where both allies are striving for greater security consultation through the bilateral Security Consultative Committee (‘2+2’) and the Quadrilateral Security Dialogue (Quad), and closer military integration in missile defence, cyber and space domains.

US President Joe Biden’s administration expressed ‘strong support for Japan’s updated national security policies as a significant evolution that bolsters Alliance deterrence’ during a recent visit by Kishida to Washington. The two allies agreed to push for integrated deterrence and greater cooperation in critical and emerging technologies. Kishida has also been visiting other Group of Seven (G7) capitals in the past few weeks seeking support for the new security strategy.

Japan is also pursuing an economic security strategy that focuses on economic resilience and supply chain security to help it weather geopolitical instability or economic coercion from adversarial countries. Japan introduced the concept of comprehensive security in the 1990s due to concerns over its vulnerability to disruptions in supplies of energy and vital raw materials.

Japan has developed and promoted military ties with a number of countries in and beyond the Indo-Pacific region. It has strengthened security cooperation with Australia and Indiaboth members of Quad alongside Japan and the USA—through high-level dialogues, joint military exercises, intelligence sharing and mutual access to each other’s military facilities. In December 2022, Japan announced a joint programme with Italy and the United Kingdom to develop a new combat aircraft and signed a reciprocal access agreement with the UK on 11 January this year, a move which China has criticized. It signed a similar agreement with Australia a year earlier.

From blueprint to implementation: Challenges ahead

Japan’s new policies represent a milestone in the country’s post-war national security strategy. However, as others have pointed out, implementation will mean dealing with some difficult issues. One is resources. Financing the new spending plans will be a major challenge and will need sustained domestic support, especially if it requires tax rises and spending cuts.

The second issue relates to whether and how the new military posture makes Japan more secure rather than places it in greater jeopardy. For all Tokyo’s insistence that its intentions are entirely peaceful, its neighbours may see its largest military build-up since World War II as a threat. Beijing has already voiced its displeasure at the new NSS, focusing particularly on its characterization of China as ‘an unprecedented strategic challenge’. North Korea and Russia have accused Japan of increasing security risks in the region with its new policies.

At the same time, potential entanglement in zones of conflict beyond Japanese territory comes with security risks that cannot be easily dismissed. And despite its security alliance and partnerships with the USA and others, much remains to be developed regarding military interoperability and joint command and control.

Finally, Japan’s new military strategy and the broader national security strategy will also need to address the complexity of dealing with the security–economy nexus. China is Japan’s largest trading partner and trade between the two is growing. This helps to explain why Japan has been less than supportive of the Biden administration’s sweeping export control measures on semiconductors. In fact, whereas Japanese–US security cooperation has strengthened significantly in recent years, progress in the two countries’ economic relationship has been slower.  

Japan evidently perceives doubling its spending on security and defence and strengthening its capability to project force beyond its borders as essential to meeting its defence needs in a deteriorating security environment. Whether it can implement these changes and what that means for Japan’s and the region’s security, only time will tell. One thing is certain: other regional powers are taking notice.


Dr Jingdong Yuan is a Senior Researcher and Director of the SIPRI China and Asia Security Programme.