Over the past decade, a more confident China has increasingly flexed its military capabilities, wielded its political influence, and deployed economic statecraft. This military, political, and economic assertiveness has led to dramatic changes in Japan’s national security risk awareness. The balance of power has begun to fundamentally shift, not only within East Asia but globally. Some scholars have argued that China has been beset by myriad serious problems, many of them of their own making. Nevertheless, China cannot be disregarded. Even now, an increasing number of countries find themselves bending to its will, a situation unprecedented in modern times. Most of Japan’s policy decision-makers believe that China poses a serious threat to Japan’s sovereign territory and its people’s lives and property—and the very liberal international order that has undergirded the nation’s security.

Japan’s concerns were heightened by the March 2021 warning by Admiral Philip S. Davidson, the (then) Commander of the US Indo-Pacific Command, that China would likely try to seize control of Taiwan in the next six years. Military activity in the Taiwan Strait has intensified in recent years, portending armed conflict to the north and prompting a review of Japan’s basic national security policies. As shown by the Japan–US summits of April 2021 and January 2022, Japan has consistently and strongly asserted the importance of peace in the Taiwan Strait. The respective foreign affairs and defense departments of Japan and the United States appear to be promoting further defense cooperation in response to perceived threats of a Taiwan Strait conflict. This is a natural development, given the high likelihood that conflict sparked by a future military confrontation could embroil Japan’s territory; the United States values Japan’s military assets as both a deterrent and as an allied force for countering threats.

Given the above, we might wonder if Japan is now in agreement with the United States concerning future policy directions toward Taiwan. While Japan’s citizens regard Taiwan positively, they remain as cautious as ever with respect to any military action. Furthermore, even if we limit our considerations to Japanese political circles—to the government and policymakers—we find that Japanese and US views toward Taiwan have not converged as much as we might expect.

This lack of convergence is partially due to the strengthening US relationship with Taiwan and sudden and significant changes in the official US language used with respect to the China–Taiwan problem. In December 2021, Assistant Secretary of Defense for Indo-Pacific Security Affairs Ely Ratner described Taiwan as “a critical node in the first island chain [in the Western Pacific], anchoring a network of US allies and partners…critical to the region’s security.” Japan has long been cognizant of Taiwan’s geopolitical importance and could scarcely be expected to disagree with this stance. However, we might ask after the intention behind Ratner’s comment, which he surely knew would be broadcast around the world. We might have similar questions about the Indo-Pacific Strategic Framework documents declassified by the outgoing Trump administration in January 2021. Specifically, we might ask what Trump hoped to achieve. In March 2021, Admiral Davidson told the Senate Armed Services Committee that the country’s “strategic ambiguity” policy had likely helped Taiwan remain independent but ought to be reassessed. In December 2021, Ratner entered the debate over whether the United States should replace “strategic ambiguity” with “strategic clarity” by publicly putting the high value on Taiwan in the US regional strategy. The intentions behind this statement remain unclear even when considered from the perspective of allied countries. It is also difficult to foresee how long this policy change on statements about Taiwan will continue.

Of course, Japanese researchers of Chinese and US geopolitics might then ask what to make of the statement in Japan’s Annual Defense White Paper of 2021 that “stabilizing the situation surrounding Taiwan is important for Japan’s security and the stability of the international community”. They might also ask how we are to understand comments made at that time by Japan’s deputy prime minister, and state minister of defense. Moreover, former Japanese Prime Minister Shinzo Abe stated that a state of an armed conflict in Taiwan would be a state of an armed conflict for Japan. However, we should assume that Japanese politicians have adopted friendly stances toward Taiwan for political gain or to gauge public opinion on potential changes in Japan’s approach to the China–Taiwan problem. The white paper’s statement did not indicate that Japan would take any specific action. Rather, Japan suggests that it would simply follow the precedent established with the expression “the Taiwan Strait”  in a Japan–United States joint communiqué. It is true that some have begun to conduct thought experiments about what Japan would do in the eventuality of an emergency. However, the answers depend on the situation in the Taiwan Strait. Biden’s administration differs greatly from the previous administration, and they could conceivably alter past policies.

What must not be misunderstood is that the United States views Taiwan as a model for successfully encouraging and establishing democracies abroad. In truth, Japan similarly views Taiwan as critical to both economic affairs and international politics. Behind this estimation we can identify the frank acceptance of Taiwan having developed its own high-tech economy, led by the manufacturing foundry of semiconductors. Similarly, Japan recognizes that Taiwan is now viewed as conforming to the value system that binds the international order. Positive sentiment toward Taiwan is strong among Japanese citizens and political circles, indicating that Japan thinks of Taiwan as a friendly place that exists in its own right, separate from the complexities of the China–Taiwan problem. Moreover, Japan broadly appreciates Taiwan’s strategic value, to say nothing of its geopolitical importance.

Be that as it may, the peace and stability of the Taiwan Strait is a pressing problem for Japan because it directly affects Japan’s existence. Thus, Japan needs to adopt an exceedingly cautious and prudent attitude in both foreign diplomacy and military policy. China is now one of the most urgent strategic problems for the United States, making Japan an indispensable partner in the Indo-Pacific region. However, we must ask whether Washington’s policymakers sufficiently appreciate how sensitive the Taiwan problem is for Japan and how the complexities of the Japanese political world are connected to this sensitivity.

Keeping in mind Japan’s situation and the Japan–US alliance, I wish to draw attention to the substantial work necessary to prepare for a potential emergency in Taiwan, given the complexity surrounding the Japanese understanding of the situation. Under its current existing legislation, Japan cannot simply deploy its military when a crisis occurs. Rather, it needs to declare a gradated state of alert, from so-called “situations that will have an important influence” to “survival-threatening situations” or “armed attack situations” (or “anticipated armed attack situations”). Japan’s capacity to smoothly declare these alert states is critical to its deployment of any armed forces. However, if we consider the domestic political situation in Japan, which has not directly faced a military emergency in the postwar era, we can see that making such declarations is no simple task. Another factor that could potentially impact domestic opinion in Japan would be joint international actions by other US allies. The political barrier to declaring a “survival-threatening situation” is significant. Joint Japan–US planning might well have contained extensive discussion of this issue; if so, such planning has not been made public, and we cannot consider it here.

Many questions surround Japan’s capacity to participate in any conflict should an emergency arise. Therefore, Japan must prepare for this possibility with reference to the numerous government and private sector simulations already being conducted. It has been pointed out that, in addition to the Japanese people, the movement of what has been described as 800,000 foreigners must also be kept in mind. Similarly, Japan must consider the evacuation of noncombatants (NEO) in light of the crucial lessons learned during US’ withdrawal from Afghanistan. We must expect that political and psychological tactics will be used during a military emergency at a scale significant enough to overthrow the government of Taiwan. We could similarly anticipate covert interventions within Japan to divide public opinion and direct it in ways that could impact the government’s ability to declare a crisis. Japan is sorely lacking in its capacity to respond to such an eventuality.

Another subject of discussion has been strengthening Japan’s relationship with Taiwan. The Japanese government has not been particularly enthusiastic about developing deeper relations with Taiwan in the past. The Japan–Taiwan Fisheries Arrangement provided a turning point, with Japan increasing its political engagement while helping Taiwan enhance its international presence. Nevertheless, it would presumably be difficult for the two countries to begin more earnest cooperation on national security. On the other hand, Japan and Taiwan could cooperate more frequently and substantially through multilateral military exercises and programs led by the US military, including programs targeted toward non-traditional  security field. Going forward, Japan will need to develop the capacity to deal with such problems as disinformation and influence operations. Given the weak military nature of these subjects, the barrier to promoting further cooperation is relatively low. However, one current issue preventing greater partnership is Taiwan’s ongoing ban on importing goods from areas damaged during the Great East Japan Earthquake. A resolution to this problem could expedite economic progress.

The points outlined above highlight the critical need for Japan and the United States to straighten out their shared understanding. This pressing need will remain, despite the US President Biden meeting with Japanese Prime Minister Kishida Fumio on January 21, 2022, to advance their “shared vision of a free and open Indo-Pacific region, which is critical to the lives of the American and Japanese peoples.” Their joint understanding will form the bedrock of trust needed to advance Japan–US cooperation. Japan’s approach to Taiwan and China remains a complex affair, prohibiting any simplistic understanding. Historically, the United States has also adopted an extremely meticulous policy stance. Both military action for the sake of deterrence and policy on public comments require exhaustive calculation agreements between allied countries. I offer this final observation for these increasingly tense times: If any player plants the idea that the situation will only deteriorate no matter what steps you take, this will only further aggravate the situation. We must be even more prudent than in the past when it comes to distinguishing necessary from unnecessary action.