Conclusion

 Conclusion

FOR MORE THAN seven decades, generations of Japanese leaders have rejected the idea that the state can and should use force to resolve its international disputes. For much of that time, deploying its military abroad was anathema, and military cooperation with the United States, its ally, was limited. Japan rearmed, but as its name implies, the Self-Defense Force (SDF) continues to be dedicated to an exclusively defensive mission. Yet it boasts considerable capabilities. Japan’s military today is a far cry from the “small but significant” military that its leaders once described. Rather, it is one of Asia’s most potent. As world spending on arms grew in 2016, Japan ranked among the top ten highest in military spending, far below the spending of the United States and China, but roughly equivalent to U.S. allies in Europe.¹

It was only in the fluid global politics after the end of the Cold War that the Japanese began to reconsider the value of their military. Many of the constraints on the SDF—imposed as a means of ensuring control over its use of force—have been lifted. For decades now, the SDF has been deployed abroad, serving in UN peacekeeping operations and other military coalitions around the globe. No longer limited to its own territory, Japan’s military has been part of a global effort to assist conflict-ridden societies in rebuilding peace, as well as a coalition partner with the United States and other advanced industrial societies in countering terrorism and piracy to maintain open access to resources from the Persian Gulf.

At home, Japan’s military is now a far more appreciated partner for civilian leaders who need its help in managing the nation’s crises. Repeated natural disasters, and some conspicuous man-made challenges to public safety, have honed the cooperation between civilian and uniformed leaders. Outside of the national government, municipal and other local leaders have worked closely with the SDF in disaster relief. Nowhere was this more obvious than in the wake of the March 2011 Great East Japan Earthquake, when the Japanese military assumed the role of first responders in the devastated Tōhoku region. For many small communities whose local governments had been literally washed away by the accompanying tsunami, the SDF took on the role of directing their crisis response until help arrived weeks and even months later. Public opinion in Japan now ranks the SDF as one of the nation’s most valued institutions.

Tokyo’s Growing Civil-Military Confidence

For much of the Cold War, Japanese decision makers defined domestic influences as the most important element in military policy-making. Indeed, it took decades for a national defense plan to emerge from the reconstituted bureaucratic processes that were designed to ensure an “exclusively defensive” military. Defeating the military’s threat-based arguments over Japan’s military aims, civilian planners instead sought to build a threat-neutral premise for military planning. The standard defense force concept (kibanteki boeiryoku) allowed for a minimal military organization that could power up should it need to, but which largely remained static in terms of its overall personnel and force posture. Instead of their own military power, Japanese decision makers looked to the bilateral framework of the U.S.-Japan alliance (nichibei taisei) to order their country’s military priorities. The new dynamic defense posture reintroduced the notion that Japan’s military readiness and capability must be premised on responding to the military capabilities of others.

While the alliance remained the frame for thinking about Japan’s external defenses, Japanese thinking about their own military power was changing. Increasingly, Japan’s conservative politicians and policy makers wanted to step up and rely less on U.S. military power. To be sure, some Japanese leaders had always wanted greater military self-reliance. As defense minister in 1970, Nakasone Yasuhiro put forward the concept of autonomous defense in response to the Nixon Doctrine. As prime minister, Nakasone argued for greater Japanese military responsibility in the alliance. Decades later, Prime Minister Abe Shinzō took up that mantle, adjusting to shifts in the regional military balance by arguing that Japan too must be more self-reliant when it comes to its defenses. But increasingly, Japan’s military was also a valuable instrument its relations with other Asian maritime states as well as with other strategic partners, such as India and the EU. No longer solely operating with the bilateral alliance, Japan’s SDF built ties with a variety of new national partners.

Along with a growing confidence in the military’s utility abroad, Tokyo became more sensitive to external threat. Reforms to the way in which military policy was made accelerated, with long-standing sensitivities over the military’s role in policy-making easing as the need for its expertise grew. New laws on how Japan might mobilize to defend itself should conflict erupt, the introduction of new technologies and new rules of engagement for their use, and the abandonment of the prohibition of defense technology competition all demonstrated how the pace of security policy reforms picked up as Japan entered the twenty-first century. What had long been seen as impossible had become routine. Japan was increasingly looking like other states when it came to government deliberations over military policy priorities.

Japan’s military too deserves some credit for this growing comfort with military policy-making. The SDF accepted its growing missions abroad with little complaint, despite the lack of public consensus. From the vintage wooden minesweepers operating without modern technology in the Persian Gulf to the Maritime Self-Defense Force (MSDF) destroyers and Japan Coast Guard personnel sent to conduct antipiracy operations in the Gulf of Aden, the Japanese maritime forces led the way in demonstrating that their country could trust them to behave abroad. Japan’s Air and Ground Self-Defense Force (ASDF and GSDF) also demonstrated their capabilities under the intense glare of domestic scrutiny in Kuwait and Iraq, respectively. Sent to these international coalitions with little support and training, the ASDF and GSDF acquitted themselves well in the midst of the far more well-equipped and politically supported dispatches of military units from a host of other U.S. allies and partners. And their role at home in disaster relief continued to build a reservoir of goodwill among the Japanese people. Once more, the Great East Japan Earthquake proved how much their country relied on them during a crisis. Yet while these internal shifts in the way Japanese relied on their military made many of the decisions possible, they were not the drivers of Japan’s changing evaluation of military power.

Japan’s leaders became acutely aware of the growing disadvantage their military was under as first North Korea and then China tested the readiness of the SDF. It was not the military’s ability to contend with the growing threat, but rather the ambiguities surrounding how and when it could act, that was at the heart of Japan’s military vulnerabilities. Hampered by an abundance of caution on the part of political leaders and by a deep-seated ambivalence built into the organizational processes for the application of military force, Japan’s military commanders sought greater clarity in how to interpret their government’s policy. As the missions assigned to the SDF increased, some of these questions had to be answered. The reinterpretation of the right of collective self-defense by the Abe cabinet in 2014 was controversial, but for a decade and a half, Japan had assigned its military abroad in coalition without giving it permission to use force in the performance of that mission. Until 2015, whether in UN peacekeeping operations, or in coalition deployments, the SDF was not permitted to use force on behalf of others.

Even at home, as the SDF was increasingly confronted with foreign militaries on Japan’s doorstep, the use of force was to be limited. Yet as the SDF was called upon to defend Japanese waters and airspace, it became clear that civilian authorities would have to rely upon their judgment. Ballistic missile defenses necessitated a high degree of readiness and the judgment of Japan’s military commander. Likewise, the experience and restraint of Japan’s MSDF commanders were relied upon to implement a “maritime security order,” whether against North Korean smugglers or Chinese submarines. The SDF became a crucial adviser as new military missions abroad were legislated and greater readiness at home was required.

As the readiness of the SDF increased in response to external pressures, Japanese political leaders showed little appetite for changing the core meaning of Article Nine of the Japanese constitution. Even Prime Minster Abe, who will likely be credited with implementing meaningful security policy reforms, never sought to transform the SDF’s defensive orientation. His proposal to revise Article Nine, adding a sentence to note that the SDF is consistent with the spirit of the constitution, simply states what most Japanese already accept. Abe is looking to settle domestic controversy rather than move the needle on Japan’s military. Some in his party want to tackle the ambiguous second paragraph and rewrite it to bolster their military’s mission as well as their name. But no one challenges the first paragraph, and there seems little political gain to be had. Incremental changes reflecting ideas already widely accepted remain the preferred mode of policy reform even for those conservatives who want a more robust use of Japan’s military power.

The SDF as an Instrument of Foreign Policy

Japanese leaders today value their military as an instrument of national policy and are far more willing to use this instrument as a means of Japan’s contribution to global security challenges than in the past. This integration of the military into Japan’s foreign policy demonstrates how Tokyo has merged the self-restraint of the constitution with its growing sense of threat perception. Embedding its military within international coalitions not only demonstrates Japan’s “proactive contribution to peace” but also ensures that the Japanese military will not be empowered to test the limits of civilian authority as it had been in the 1930s. Cooperative security—even in the defense of Japan—has been the preferred means of using military force. Going it alone militarily is no longer a Japanese preference.

The United States and other nations in Asia and Europe also see Japan’s military as an asset in collective responses to global terrorism and piracy as well as in maritime challenges across the Indo-Pacific. This new post–Cold War effort to build military coalitions has created opportunity for the SDF to represent its nation’s desire to assume greater responsibility for global security. Moreover, closer to Japan’s own interests, the MSDF has been given far more latitude to assist in collective efforts to patrol sea lanes and ensure stable access to resources transiting through Asia’s waters all the way to the Middle East.

Japan’s leaders may increasingly use the military as an instrument of national policy, but they continue to shy away from difficult choices when it comes to planning for the use of force. Political elites champion civilian control but largely refuse to debate military policy in the Diet; they argue for international security cooperation but stop short of embracing the full responsibility of collective security; and they embed the SDF in coalitions abroad but micromanage from Tokyo its use of weapons in the face of danger. Adapting to the accelerating shifts in the military balance will require a firm political consensus on the use of force, and politicians will need to explain to the Japanese public the trade-offs ahead should their security environment worsen. To make the military a more effective instrument, Japan’s politicians will need to embrace its role as a warfighting organization in addition to its role in keeping the peace.

While Japan’s leaders have expanded their use of the military as an instrument of national power, the SDF has never fought a military conflict. Thus Japan’s military policy choices are anticipatory; imagining how war might arrive on Japan’s shores has largely been the task at hand for civilian leaders. Yet it seems increasingly likely that decision makers will need to order their military to use force. Asia’s military balance is changing rapidly, and Japan is increasingly at a disadvantage. North Korea’s growing arsenal of missiles and weapons of mass destruction as well as China’s expanding maritime capabilities are changing Japan’s defense requirements. As Japan’s security and status have seemed jeopardized, its political leaders have gradually allowed their military to contribute to global security challenges and to improve their own defenses. Evidence of this can be found in the decision-making on sending the SDF abroad, crafting contingency laws to prepare for a military crisis, deliberating a revision of the Japanese constitution, and upgrading U.S.-Japan alliance coordination.

Threat Perception and Military Readiness

The Japanese state has also prepared itself for the possible use of force in and around its territory. The rising military capabilities of its neighbors have heightened the sense of threat in Tokyo, leading to significant investment in new defensive weapons and in enhanced refinements to the defense coordination between the United States and Japan. Preparing for war has also meant considerable reforms within Japan, improving planning across government ministries but also building relationships and plans with local authorities and the SDF. Civil warning systems, long used only for natural disasters, have now been used for North Korean missile tests. Preparing both the Japanese military and the Japanese people is now part and parcel of Japanese defense planning.

Japanese military planning increasingly focuses on ensuring the U.S.-Japan alliance is ready to cope with any contingency in and around Japan. New scenarios are now driving alliance planning. North Korea’s new missile capabilities have brought Japan within range of Pyongyang’s direct attacks, a fact that Kim Jong-un has been eager to demonstrate since 2016. Moreover, these missiles now launch without much warning from difficult-to-detect mobile launchers, using solid instead of liquid fuel.² Just as challenging for Japan’s defenses is the growing maritime presence of the Chinese military and paramilitary in and around Japanese waters. Beijing’s challenge of Tokyo’s administrative control over the Senkaku Islands adds greater urgency to the SDF’s island defense mission. Both of these new threats have prompted a revision in the bilateral guidelines for military cooperation between Japanese and American militaries.

As others in Northeast Asia deploy greater military forces near Japan, crisis management is a high priority for the alliance. Notionally, the U.S. military has long been embedded in Japan’s defense planning, especially for a possible conflict on the Korean Peninsula. But beyond this defining flashpoint in Northeast Asia, China’s rise has increased tensions and complicated planning. After the island clash between Japan and China in 2012, the U.S. and Japanese governments created a new mechanism to facilitate crisis management.

Assigned to missions once thought to be beyond its responsibility, Japan’s military has adapted and learned as it deployed abroad and as it confronted foreign armed forces in Japanese waters and airspace. As the SDF has learned from these missions, so too have Japan’s civilian bureaucrats. More and more, the unique contributions that the SDF can make in cooperation with other national militaries abroad have become a valuable asset to Japanese diplomacy. Within Japan, the SDF’s work with the national police, the Ministry of Foreign Affairs, the Japan Coast Guard, and the Japan International Cooperation Agency has led to partnerships among agencies that had long been suspicious of association with the military.

Similarly, the need for professional military expertise in handling Japan’s rising regional security challenges has grown. For much of the Cold War, threat perception had been dismissed as a driver of military planning; few saw a direct military threat to Japan, and many across the Japanese government still saw the need to avoid an unbridled increase in military capabilities. Budgets were limited for precisely the same reason. The military voice in policy-making was limited to within the Defense Agency. But growing concern over the military buildup by countries surrounding Japan created more interest in the military perspective on policy choices. Within the Ministry of Defense, the balance of professional responsibility for the nation’s defenses now rests more equally between civilian and uniformed policy makers. Across the Japanese government, other bureaucracies work regularly with their nation’s military. The Ministry of Foreign Affairs sees in the SDF a welcome partner for global cooperation, especially in the UN; the Ministry of Economy, Trade and Industry now works closely with it on defense industrial cooperation; and the Ministry of Finance depends on the uniformed military’s assessments as much as civilian planners when it decides on Japan’s budgets.

Reassessing the U.S.-Japan Alliance

Old habits in alliance policy-making also began to change. Washington had long demanded more in the way of defense spending and SDF capabilities. While this refrain was also heard in other alliances with South Korea and Europe, Japan’s unique military restraints shaped that burden-sharing conversation through the end of the Cold War and into the decades that followed. Yet Tokyo faced an uncomfortable wake-up call in the first Gulf War. No longer would spending money in lieu of military action be sufficient. The George H. W. Bush administration began to argue that the time had come for Japanese “boots on the ground,” a refrain also heard in other discussions with U.S. allies. Japan could no longer sit out of the military coalitions formed to cope with security threats globally, even as it increasingly upped its host nation support (HNS) for U.S. forces stationed in Japan. Japan’s military support in a volatile Middle East became just one more metric for gauging reciprocity in the alliance, and by implication the ticket Tokyo needed to ensure continued U.S. support for Japan’s own security.

Tokyo had never had to test the proposition that Washington would assist Japan if attacked. Article Five of the 1960 bilateral security treaty pledged U.S. defense assistance, and yet Japan seemed safe from direct threat or attack. The flashpoints of Asia were elsewhere—on the Korean Peninsula or across the Taiwan Strait. Relatedly, the U.S. nuclear umbrella was rarely discussed during the Cold War, especially in front of the Japanese public. But the reduction in U.S. nuclear forces after the Cold War worried Tokyo as it became clear that China remained committed to modernizing its nuclear arms and North Korea pursued its own nuclear arsenal. Ensuring that the nuclear umbrella was up to the task became more and more pressing for Tokyo, and so too was the need for the United States to declare its intentions to defend Japan in the face of increasing military assertiveness from both Pyongyang and Beijing.

The island dispute with China fundamentally changed Tokyo’s perceptions of the alliance. Chinese pressure on the Senkaku Islands had escalated by 2012 as Beijing deployed maritime forces to the vicinity of the islands. For the first time, it was possible to imagine that Japan and China might find themselves at military loggerheads over these small, isolated islands. While no one wanted war, there was a risk that an incident or miscalculation by a local commander could set off a broader conflagration. In short, Japan could find itself at war with China. U.S. military support would be critical, and yet the two allies had never imagined this scenario, let alone practiced for it. Indeed, Japanese leaders had been loath to consider a direct Japanese military role in a conflict with China despite repeated crises across the Taiwan Strait. The Senkaku tensions offered a different scenario, one that involved an initial military response by Japan to be followed by a call for U.S. help. Military planners and politicians alike have shifted from worrying about being entrapped in U.S. wars elsewhere in the region to focusing more about ensuring the United States does not abandon Japan in a military confrontation with China. With U.S. forces forward deployed on Japanese bases, assistance could be easily provided. The critical question, however, was whether the United States would use force on Japan’s behalf even if it meant going to war with China.

Tokyo has gone from being a hesitant military partner to being an advocate for military readiness. While polls reveal the Japanese regard with favor the U.S.-Japan alliance, Washington and Tokyo have not always agreed on strategic priorities. In the wake of the 9 / 11 terrorist attacks on the United States, Japanese governments had to advocate more strenuously for their interests, as the wars in Iraq and Afghanistan drew U.S. attention away from the Pacific.³

In Northeast Asia, Tokyo also saw its security priorities differently from Washington, causing some policy dissonance over how to cope with a changing region. On North Korea, for example, the George W. Bush administration’s effort to pursue six-party talks left many in Tokyo concerned, especially about the prominent role China was assigned in the process. Perhaps the most challenging problem for Tokyo has been the deterioration of its relationship with Beijing and Beijing’s assertive demonstration of its growing military interests in the East China Sea. China’s rise has revealed differences over the geopolitical future of the region, and as Japan’s relationship with a more assertive China has grown more difficult to manage, Tokyo has been forced to rely on Washington to advocate on its behalf with Beijing. Sensitivities to Washington’s susceptibility to Beijing’s plans in Asia have deepened.

On top of these strategic sensitivities in Asia, Tokyo—along with other U.S. allies—was startled by the tenor of the 2016 presidential election. Candidate Donald J. Trump suddenly raised fundamental questions about the future of U.S. policy toward Asia and about the U.S.-Japan alliance. For the first time since the 1960 security treaty was signed, a candidate for president openly questioned the value of the alliance to the United States. During the campaign, the Republican nominee raised alarm in Tokyo when he repeatedly mentioned Japan as an unfair trading partner, but his comments on the alliance were more worrisome. In a March 2016 interview with the New York Times, Trump argued that perhaps the time had come for Japan and South Korea to go it alone in defending themselves against North Korea. Trump also took aim at the Japanese contribution to U.S. forces there. Even after being told that Japan pays around 50 percent of the HNS costs, the highest amount of any ally, Trump responded by suggesting that Tokyo foot 100 percent of the bill.⁴

In Tokyo, senior officials responded promptly. Chief Cabinet Secretary Suga Yoshihide spoke first publicly, stating, “Whoever becomes president of the United States, the Japan-U.S. alliance, based on the bilateral security agreement, will remain the core of Japan’s diplomacy,” and Japan “will maintain its Three Non-Nuclear Principles”—not possessing, producing, nor permitting the introduction of nuclear weapons to Japan. Foreign Minister Kishida Fumio, a native of Hiroshima, echoed this rejection of nuclear weapons: “Japan abides by the Three Non-Nuclear Principles and the Atomic Energy Basic Act, and emphasizes the framework of the Nuclear Non-Proliferation Treaty. Therefore, I do not see any possibility of Japan possessing a nuclear arsenal.” In the Diet, the Abe Shinzō cabinet was also confronted with questions about the Trump candidacy and what it meant for alliance policy. The prime minister was deeply committed to the Trans-Pacific Partnership, the twelve-nation trade agreement that the Obama administration had advocated, and he had initiated Diet ratification procedures in the hopes of providing momentum for a U.S. ratification process at the end of 2016. On the issue of the HNS and Trump’s call for reciprocity, however, defense policy makers were clear that they had little appetite for increasing Japanese spending on U.S. forces even after Trump was elected. Instead, the incumbent defense minister and several former defense ministers argued for greater military self-reliance within the alliance. Defense Minister Inada Tomomi stated that this election result “provided the opportunity to think more seriously about what Japan could do on its own to defend itself.” Former defense ministers Ishiba Shigeru and Onodera Itsunori made a similar case for how to manage any possible calls for Japan to increase its HNS; given the increasing military pressures on Japan, the SDF rather than U.S. forces would be more appropriate recipients of Japanese taxpayer money.⁵

Just as in previous transitions between U.S. presidents, the transition from Obama to Trump raised questions not only about the alliance but also about U.S. policy toward Asia. The Japanese government welcomed Obama’s emphasis on a rebalance of U.S. foreign policy priorities to the Asia Pacific wholeheartedly, but as Tokyo’s relations with Beijing soured, sensitivities in Tokyo about the Obama approach to China deepened and led them to question how this new U.S. Asia strategy was to be implemented.

Trump’s campaign slogan “America First” raised far different concerns, however; would this mean a more isolationist approach to foreign policy or a more interventionist approach? Would trade conflict with China erupt at the cost of strategic cooperation among allies in Asia? Prime Minister Abe’s quick move after the election to meet with then President-elect Trump, stopping off in New York on his way to the annual Asia Pacific Economic Community summit in Lima, Peru, suggested that the tenor of the campaign and especially Trump’s focus on Japan had alarmed him.

While Abe’s personal diplomacy seemed to reassure the Japanese government that President Trump would not be antagonistic toward the alliance, Trump’s willingness to shake up U.S. relations with China as the president-elect introduced yet another variable into alliance management. Trump accepted a congratulatory phone call from Tsai Ing-wen, the president of Taiwan, on December 2, 2016, and became the first U.S. president-elect ever to have direct contact with a Taiwanese leader after 1979. Trump then went on to tweet his willingness to challenge the “one China” policy in the face of criticism. China responded quickly and harshly, and suddenly Tokyo began to wonder if a Trump administration might be too risky in its management of China.

As the Trump administration started out, however, it was the familiar challenge of North Korea that returned the alliance to steadier ground. During his visit to the United States, Abe met with Trump in Washington and issued a joint statement that reiterated U.S. support for the Senkaku Islands and for the broader security cooperation in the alliance. Moreover, the two leaders announced that they would initiate a separate dialogue on economic cooperation, led by Vice President Mike Pence and Deputy Prime Minister Asō Tarō. During the prime minister’s visit to the president’s estate in Florida, Pyongyang once again tested a missile aimed in Japan’s direction, prompting the two leaders to call a press conference to protest this violation of the UN Security Council’s most recent resolution. President Trump, standing with Prime Minister Abe, declared that the United States “stood behind Japan, 100 percent” in its efforts to defend itself against Kim Jong-un’s provocations.⁶

North Korea’s pressure on Japan’s missile defenses prompted serious consideration of the ability to retaliate and has given Japanese planners even more reason to invest in their military capabilities. But the growing capabilities of Pyongyang have only exacerbated Tokyo’s concern about the reliability of the U.S. extended deterrent. The Trump administration’s initial tough stance on sanctioning North Korea was welcomed by the Abe cabinet. Indeed, Abe worked hard to support the UN Security Council’s tough reckoning with North Korea on the costs of its threat to global security. Moreover, Tokyo was quite willing to up the military coordination with Seoul and to synchronize its military exercises with the United States to demonstrate just how lethal the combined forces of the United States and South Korea could be if threatened. But the abrupt diplomatic shift to diplomacy by President Trump caught Abe off guard, coming just weeks after the prime minister had traveled to the United States to confirm that the United States and Japan were on the same page when it came to the North. While publicly the Japanese government supported the idea of a negotiated denuclearization, the unpredictability of the U.S. president at the negotiating table was worrisome. Few in Japan felt that its interests would be adequately represented in the unfolding summitry with the North Korean leader, and Abe began to seek his own meeting with Kim Jong-un. With the increasing demonstrations of military force in Northeast Asia, Japan’s strategic dependence on the United States deepened, and yet the Trump presidency had made the United States a far less reliable ally.⁷

A Look Ahead

The growing military power of China and North Korea create pressures on Japan’s defenses, and the unpredictability of decision-making in Washington raises new concerns about the future of the U.S.-Japan alliance. The Trump administration’s call for greater allied burden sharing has led the Abe cabinet to consider how to up its spending on U.S. weaponry and to increase its military spending over the next five years. The midterm defense plan that will begin in 2019 is expected to increase military spending by at least 1 percent annually, a hefty increase by Japanese standards. But it is unlikely that this will significantly alter the way in which the SDF is armed, nor will it massively increase the size of Japan’s military forces. For all of the recent changes in Japanese security planning, including the focus on military readiness, Japan’s military continues to be organized for self-defense. Military capability—even the recent consideration of conventional strike forces—is still considered as a means to deter aggression. Developing a retaliatory capability is seen as the best means of ensuring neighboring countries will think twice before using force against Japan.

As tensions continue to rise in Northeast Asia, all eyes—in particular outside Japan—have been on Prime Minister Abe Shinzō and his security reforms. These reforms have been rolled out one after another under Abe, in a seeming cascade of security policy transformation. Yet many have been in the making for years. Moreover, despite Abe’s efforts to fix the legal problems facing Japan’s military, the political sensitivity over the use of force by the SDF—when and if it can use its weapons beyond Japanese territory—remains. No change has been made yet to the premise that the SDF will respond to violence only after Japan has been attacked. Early thinking on acquiring missiles, for example, considered preemptive strikes on missile launch pads, but with North Korea’s move to mobile launchers, this no longer seems realistic. To date, Tokyo’s discussion of acquiring potential retaliatory capability has been justified in terms of self-defense. But the use of this capability is liable to become just as conditioned by Diet concerns over the initiation of use of force.

Changes to Japan’s policy on the use of force have largely been additive rather than innovative. Few in the Diet want to send the SDF to missions where it will need to use force, and an additional condition on its deployment, even within UN peacekeeping operations, is to keep the Japanese military far from situations where it may actually need to shoot. The South Sudan deployment, instead of facilitating SDF action on the ground, seemed just as hesitant regarding its role as in previous UN peacekeeping missions. The burden on others to provide the firepower needed to protect Japanese troops makes their utility in UN operations limited. In coalitions organized for collective security, the expectation is that all militaries will be able to use force if needed. Japan remains a reluctant partner still.

The Japanese public remains sensitive to the possibility of military action abroad. The SDF too have become accustomed to this low-risk conditioning of their overseas deployments. No member of the SDF has died abroad, while Japanese police, diplomats, and aid workers have lost their lives. Should Japan’s military be found wanting in response to a dangerous situation abroad, or should the situation end up costing SDF lives, the Japanese will have to decide if they are ready to accept that. If the SDF is to be effective in international military coalitions, it will need to be able to confront risk.

Defense of the Japanese islands, however, will be expected. None of the legal changes made recently have fundamentally altered Japan’s desire to limit the use of military force to tasks that enhance its own security. Improvements in Japan’s defense preparedness have been made, and the learning over time has proven invaluable to the discussions of how to improve and support the SDF as it prepares to confront North Korean and Chinese militaries. New capabilities—such as counterterror and amphibious units as well as Japan’s new ballistic missile defense systems—are being developed, and additional capabilities are under consideration. Japan continues to upgrade its military technologies and to expand its cooperation with others in the Asia Pacific.

Little public attention has been given to whether the SDF is ready to fight, and win, a war, however. For the SDF, there is no comfort in the notion that the best defense might be a good offense. None of the new missions for the SDF involves coercion or punishment of other states. Preemption as a military tactic is still denied to the Japanese military. Even the call for an independent military strategy—a hedge against the possible decline in U.S. strategic protection—is absent in today’s debate. If anything, Tokyo’s security planners and the Japanese public seem to have doubled down on their investment in the alliance with the United States. Neither growing external pressures on Japan’s defenses nor the worry about declining U.S. interest in alliances seems to have jolted the Japanese commitment to limiting their use of military force.

Japan’s military today, however, is more thoroughly integrated into national strategy than ever before. Four generations of military leaders have now emerged at the top of the SDF, many who trained alongside U.S. forces or other national militaries in a variety of missions. The SDF’s responsibility for—and responsiveness to—the Japanese people has been amply demonstrated in a series of natural disasters and other crises, and Japan’s government today is much better prepared to deploy and support it. Hostile military action against Japan, of course, will present the ultimate test of the SDF and its growing capabilities. Japan’s doctrine of military restraint works so long as there is no advantage to testing its military or its alliance with the United States; but it may not be effective if and when it becomes evident that others see the possibility—and the benefit—of coming out ahead by using force against Japan.

Worrisome signs are ahead. The U.S.-Japan alliance, while still embraced in Tokyo, seems less certain in Washington. Without a doubt, the cost of Japan’s strategic bargain with the United States is rising, but the currency may also be changing. Burden-sharing debates are not new, but what is different today is this questioning of alliance equities that comes as Asia’s balance of power is changing. China’s military power is on the rise and increasingly felt in Asia—and cross the Indo-Pacific. The fate of U.S.-Chinese relations could unsettle Japanese calculations. A tougher U.S. line on China is welcome in Tokyo, but a downward spiral in relations between Washington and Beijing could easily produce a heated arms race, or worse yet, direct confrontation between the two major powers in Asia. Japan would be called upon to fight in that conflict, should it become a reality. Japan’s vulnerability to missile strikes was laid bare in 2017 by North Korea—a fact that few in the region failed to notice. Only Tokyo has no ability to deal a serious military blow to a neighbor in a region of the world where the major powers intersect with often competing interests. Russia to the north, China to the east and south, and both nations on the Korean Peninsula are warily eyeing each other’s militaries. Japan may not share a land border with any of these nations, but it has no real defenses against their ballistic missiles, and, without a robust U.S. defense of its interests, it is vulnerable to coercion by the nuclear weapons states. Deterrence may require another look at Japan’s postwar doctrine if the United States no longer offers an unflinching willingness to strike on Japan’s behalf.

Japan’s preference for limiting its use of military power shaped more than seventy years of its strategy. In many ways, this reassured the Japanese as well as their neighbors. Three generations of civilian and uniformed policy makers gradually developed a more comfortable policy-making process on Japan’s military aims and its capabilities, one responsive to elected leadership and one where those who wore the SDF uniform built strong ties with their communities and the citizens they serve. Yet as the United States becomes far less predictable and as Japan’s neighbors reach far more readily for their military to demonstrate power, limiting Japan’s military power may no longer make Japanese feel safe. Even Japan will find it necessary to assert its military power in this newly fraught Asia.