Publication of working papers for the SPF project “Shaping the Pragmatic and Effective Strategy Toward China”

 IINA (International Information Network Analysis) will upload the working papers written by U.S. and Japanese project members focusing on shaping a pragmatic and effective strategy toward China. We hope that this series will help IINA readers understand how experts from the U.S. and Japan see China and the U.S.-Japan joint efforts, which have the potential to determine the future world order.


Japan and the U.S. are becoming increasingly concerned about a Taiwan contingency. Chinese Premier Li Keqiang, in his report on government activities at the National People’s Congress delivered on May 22, 2020, removed the word “peaceful” from the section addressing “reunification” with Taiwan, suggesting a possible change in policy[1].

Elsewhere, the China policy of the new administration of U.S. President Joe Biden, who took office this year, has drawn scrutiny. While the Biden administration has changed many of policies of the previous Trump administration, it made clear that it would maintain its predecessor’s tough position on China[2]. At a U.S. Congressional hearing in March, Philip Davidson, then commander of the Indo-Pacific Command, said that a Chinese invasion of Taiwan could happen in the “next six years,” and his successor, John Aquilino, said it is “much closer to us than most think”[3]. Behind these concerns, there are also worries about the delayed deployment of U.S. military forces in response to China’s growing military power[4]. According to a comparison of U.S. and Chinese forces in the Western Pacific as of 2025, China is expected to have three aircraft carriers deployed to the U.S.’ one, 108 multi-functional warships to the U.S.’ 12, six times as many submarines, and nine times as many warships. Regarding fighter jets, China has 1,250 fighters compared to the U.S.’ 250, and it plans to have 1,950 by 2025, nearly eight times more than the U.S. total. Additionally, China’s ballistic missiles also pose a major threat to naval forces approaching the area.

The U.S. overall has an advantage over China, including Washington’s 11 aircraft carriers, but even if it deploys forces from the west coast or Alaska, it would take two to three weeks for them to reach the first island chain that stretches from the Japanese archipelago to Taiwan and the Philippines. That makes it difficult to overcome the numerical advantage China maintains by virtue of geography. Given these conditions of relative power, it is no longer feasible for the U.S. alone to support Taiwan in the event of a contingency. Japan, which hosts important U.S. military bases, is in a position to take part in such an event.

In this context, Japan and the U.S. emphasized the “the importance of peace and stability in the Taiwan Strait” in the joint statement at the March 16 “two-plus-two” meeting (security consultations between the foreign and defense ministers), and then went further at the April 16 leaders’ summit, adding the phrase, “encourage the peaceful resolution of cross-Strait issues.” This was the first time since 1969, before the normalization of diplomatic relations between Japan and China, that “Taiwan” appeared in the joint statement from a Japan-U.S. leaders’ summit.

With the U.S. and China continuing to increase their freedom of navigation (FON) operations and pressure on Taiwan respectively, this article will review Japan’s legal framework for addressing contingencies, and then, with a Taiwan contingency in mind, examine Japan’s response to each stage of a crisis as it develops from its initial stages into armed conflict, and what it should do to prepare.

2.Japan’s contingency legislation system

The actions of the armed forces of other countries generally involve cross-sectional responses to situations ranging from peacetime to wartime. In contrast, the actions of the Japan Self-Defense Forces have adopted a legalistic approach that does not allow for actions other than those enumerated types and authorities. For situations that affect Japan’s peace and security, it is designed as a “contingency management system” that classifies responses according to the situation.

Japan’s development of laws to handle “contingencies” is the result of the post-Cold War shift of threat probability from direct armed attacks against Japan to emergencies occurring in the area around the country that could then spread to Japan. In 1997, the Guidelines for Japan-U.S. Defense Cooperation were revised to reflect greater focus on situations in areas around Japan, rather than the previously imagined contingency in Japan itself, and in 1999, the “Emergency-at-Periphery Law” was established. In 2003, the “Armed Attack Situation Response Law” was established to provide a framework for dealing with armed attacks, an area that had been neglected for roughly 50 years after World War II.

In the Peace and Security legislation that came in response to the 2015 revisions to the Japan-U.S. Guidelines, the “Law on Important Influence Situations”[5] was amended to remove the limitations in the Emergency-at-Periphery Law that restricted the scope of responses to the area around Japan. The 2015 legislation also added “survival-threatening situations,” which allow for collective self-defense on a limited basis, to the Armed Attack Situation Response Law, which is premised on the exercise of individual self-defense only. With this, there are five categories of situations that could impact Japan’s peace and security: “critical impact situations,” “emergency response situations,” “anticipated armed attack situations,” “armed attack situations,” and “survival-threatening situations.” The changes also laid out “joint international peace response situations,” in which Japan proactively addresses situations that threaten the peace and security of the international community[6].

The measures taken by the SDF in each situation are broadly classified into "important influence situations," "emergency response situations," "anticipated armed attack situations," and "joint international peace response situations," all of which do not involve the use of force. There are also "survival-threatening situations" and "armed attack situations," which do involve the use of force and require authorization from the Diet.

3.Different scenarios and Japan’s responses

A Taiwan crisis is not expected to be classified as a “ship inspection operation” based on economic sanctions, or a “joint international peace response situation,” which would not directly affect Japan’s security. It would instead likely be categorized as a “important influence situation” or a “survival-threatening situation,” depending on circumstances. Furthermore, if the situation spread to Japan, it would be recognized as an “armed attack situation.” However, considering Japan’s political environment, with its still deeply rooted “pacifism” and “consideration for China,” it is not always simple to immediately apply institutional categorizations for situations to reality. Therefore, the following is a discussion of Japan’s response to each scenario.

1) Before armed conflict

Currently Japan and the U.S. are conducting ongoing vigilance and surveillance in the East China Sea and sharing information. Therefore, if the U.S. deploys troops in the vicinity of Taiwan, both Japan and the U.S. will strengthen their vigilance and surveillance in the East China Sea, or, depending on the concentration of U.S. troops around Taiwan, the SDF will strengthen its current vigilance and surveillance in a supplementary manner.

If the U.S. concentrates its forces in the waters around Taiwan, supply support for the troops will be essential. If the situation turns tense, one cannot expect the ASEAN countries, which are concerned about their relations with China, to permit U.S. ships to make port calls for supplies. The U.S. forces may stop in Taiwan, but if their deployment is prolonged, they will need supply support at sea. In this case Japan’s support will be indispensable, as it can send supply forces back and forth from nearby Okinawa. In this case, if Japanese and U.S. troops are "both on the ground" and conducting vigilance and surveillance, supply support based on Article 100-6 of the Self-Defense Forces Law is possible, but if U.S. troops take independent action in the waters around Taiwan, Japan must recognize an "important influence situation" to provide support. Additionally, the declaration of a “important influence situation” allows for relevant administrative organizations other than the SDF to take “response measures,” and requests for cooperation from entities other than the government can be made[7].

2) Development into a U.S.-China armed conflict

If the situation develops into an armed conflict, the “important influence situation” would continue if already declared, or one would be declared if it had not been so already. Japan would support the U.S. forces that have become party to the conflict (and those of other countries participating). However, under a “important influence situation” the SDF will be unable to take “response measures” at the site of actual combat operations[8], nor will it be able to “defend U.S. forces.” Article 95-2 of the SDF Law, which is the basis for "defending U.S. forces," stipulates that the "protection of U.S. forces shall exclude locations where combat activities are currently occurring," and an attack on U.S. forces at this stage is itself a "combat activities”[9]. But with the reported threat of China’s anti-ship missiles, missile protection by the SDF will be an important form of support. Therefore, if the protection of U.S. forces is required, it is necessary to immediately declare a “survival-threatening situation.” However, even in the case of a "survival-threatening situation," Japan's exercise of collective self-defense is, according to the government's view, thoroughly limited in scope, and does not involve full-scale combat operations such as those conducted by multinational forces in the Afghanistan and Iraq wars. In principle, it is limited to logistical support, search and rescue of combatants in distress, and the protection of U.S. troops and equipment involved in combat.

3) China’s attack spills over to Japan

The U.S. forces dispatched to the area around Taiwan will primarily consist of troops from U.S. military bases in Japan, such as Okinawa, Yokosuka, and Sasebo. In addition to the U.S. bases, Japanese ports and harbors, which are important rear bases, could become targets of Chinese attacks. In this case, Japan can declare an “anticipated armed attack situation” and issue a “defense convocation order” and a “standby order for deployment.” Furthermore, Japan could recognize an "armed attack situation" and order a "defense deployment" when there is a clear and imminent danger of an armed attack, and it could invoke the right of self-defense when an armed attack occurs[10]. In invoking the right of individual self-defense, the restrictions of a survival-threatening situation are removed, and the use of force as a party to a general armed conflict becomes possible.

4.Additional challenges — the evacuation of non-combatants in a Taiwan contingency

Another important topic related to a Taiwan contingency must be addressed: “non-combatant evacuation operations” (NEO), which became a major issue in August for countries operating in Afghanistan.

1) NEO in Taiwan

Taiwan has multiple international airports that can accommodate large commercial aircraft, as well as many regional airports with short runways that are scattered throughout the island for domestic flights. This would allow for military transport aircraft capable of short takeoffs and landings to conduct evacuations from regional airports in the event that circumstances turn tense and commercial charter aircraft operations are temporarily congested. However, a critical problem with the use of airports is that they become targets for attacks by China. Both the military and civilians sectors operate out of many of Taiwan’s airports, and in wartime civilian airports can be used for military purposes. This inevitably makes all airports attack targets, and renders evacuation from them almost impossible.

However, being surrounded by the ocean, maritime evacuation from Taiwan is possible. Maritime evacuation would be carried out by ships with large carrying capacity, and, unlike with aircraft, large numbers of people could be evacuated at once. Moreover, evacuation by sea is the only means available when airports are inoperable, or to supplement airports when their use is limited because excessive amounts of commercial aircraft are landing. Maritime evacuation is not limited to ports, but can also include shuttle transportation via helicopter, meaning there are few limitations on where evacuees can gather and ships can wait. There is, however, a limit to the number of forces, particularly helicopters, that can be deployed in a such a scenario.

Along with the U.S. Navy’s aircraft carriers and landing crafts, which provided support after the Great East Japan Earthquake in 2011, Japan has four destroyers capable of carrying large helicopters and three transport ships in the region. These forces can be expected to be the mainstay of Japan-U.S. NEO operations in the event of a Taiwan contingency.

2) The possibilities and limits of Japan’s NEOs in a Taiwan contingency

In the past, Japan has asked the U.S. and European countries to evacuate Japanese nationals from locations that are distant from Japan, such as parts of Europe, Africa, and the Middle East. These countries have been willing to comply with Japanese requests in accordance with international conventions. However, this relationship will be reversed in the case of a Taiwan contingency. European countries, which have played important roles in NEO operations in Europe, the Middle East, and Africa, do not have bases of operation in this relatively distant region. The evacuation of their citizens will inevitably fall to the U.S. and Japan, which have advanced operational capabilities and bases nearby. The question is whether Japan will be able to adequately respond to these requests.

Japanese NEO operations are provided for in the SDF Law as “measures to protect overseas Japanese nationals, etc.”[11] and “the transport of overseas Japanese nationals, etc.,”[12] but the content of these provisions is generally more limited in important areas than NEOs conducted by other countries because of Japan’s constitutional restrictions.

“The transport of overseas Japanese nationals” was added to the SDF Law in 1994. At that time, there was still strong resistance to deploying the SDF overseas. Because of this, the law includes a provision that the “safety of transport” must be secure to ensure there is no possibility that would lead to the use of weapons. This greatly limited the scope of operations, including what people and equipment can be transported, in a real situation. Although these restriction have since been amended to better reflect the reality of NEO operations, limitations on “transport” remain, such as “transport must be carried out safely” and “with the consent of the other country.” In this context, the four cases of “transporting Japanese nationals, etc.” to date have been small-scale, involving less than 10 people[13]. Afghanistan, the fifth such case, involved only one Japanese national and 14 Afghans.

In addition, the 2015 Security legislation added “measures to protect Japanese nationals, etc.” to the SDF Law, enabling not only transport but also the elimination of transport obstructions and the protection and rescue of Japanese national who may be in danger. However, these “protective measures” are also limited to places where the national authorities maintain control and no combat activities are occurring, and the consent of the other nation is also required. In other words, real NEO operations are extremely limited. In Afghanistan, “protective measures” were not implemented beyond the airport because the requirements were not met.

It must, therefore, be said that there is a considerable gap between the NEOs conducted by the SDF and the NEOs conducted by other countries.

Furthermore, article 84-4 of the SDF Law states that non-Japanese nationals to be transported are “transported together(同乗させること) at the request” of the minister of foreign affairs. As written, the phrase “transported together” means that the law does not allow for non-Japanese nationals to be transported alone, and conditions are only satisfied if at least one Japanese national is also to be transported. However, in the case of Afghanistan, only Afghans were transported on Aug. 26. This was the first time that non-Japanese nationals were transported, and it set an important precedent: It showed that although SDF aircraft cannot be dispatched to a foreign country to transport only non-Japanese nationals, aircraft dispatched for the purpose of transporting “Japanese nationals, etc.” can transport only non-Japanese nationals and meet the requirement of “riding together.” However, deployments explicitly for the purpose of transporting only non-Japanese nationals are not possible, and there is no legal basis for responding to international NEO requests from other countries to transport only non-Japanese nationals.

3) Japan-U.S. NEO collaboration in a Taiwan contingency

In the 1997 revisions to the Japan-U.S. guidelines, which were focused on the Korean Peninsula, the phrase “noncombatant evacuation operations” appeared for the first time, and it remained in the 2015 revisions. The guidelines state, “As appropriate, the two governments will coordinate in planning and cooperate in carrying out evacuations of Japanese or U.S. noncombatants. These evacuations will be carried out using each country’s capabilities such as transportation means and facilities in a mutually supplementary manner.” In addition to stipulating that each country is responsible for evacuating its own nationals, the guidelines address third-party cooperation, stating, “The two governments may each consider extending evacuation assistance to third-country noncombatants.”

According to data from the Taiwanese authorities[14], at the end of July 2021 there were 779,908 foreign residents, of which about 15,000 are Japanese. Just over 36,000 of which are from countries outside of Asia, led by about 10,000 Americans. The total number of residents from Indonesia, Vietnam, the Philippines, and other Asian countries exceeds 580,000, accounting for 75% of the island’s foreign population. These countries do not have the capacity to evacuate their own citizens, so it will be necessary to respond to their NEO requests. Furthermore, if combat breaks out on Taiwanese territory, it will become necessary to evacuate Taiwanese residents, who will not be able to flee the island themselves. If Taiwanese requests are added, the number of NEOs could be unprecedented.

In this context, if Japan and the U.S. jointly conduct NEOs in a Taiwan contingency, and, in line with the Japan-U.S. guidelines, they extend aid to third countries, it will be necessary for the U.S. to fully understand the restrictions facing Japan before proceeding with coordination: The U.S. military has a great deal of experience conducting large-scale NEOs, including Operation Sharp Edge in Nigeria in 1990, while the SDF has little experience and lacks a legal basis for transporting “only non-Japanese nationals.”

In the event of a Taiwan contingency, Japan’s inadequate legal framework for the evacuation of both Japanese and non-Japanese nationals will pose a major problem not only for Japanese living in Taiwan, but also for Japan’s ability to contribute to the broader international community. This is an urgent issue facing Japanese political leaders and they should not delay in addressing it.

4) Challenges with NEO

Japan’s contribution to an NEO in a Taiwan contingency would not end with transportation. At the time of the U.S. NEO in Afghanistan, 12 countries from Europe and the Middle East allowed U.S. military evacuation flights in transit to land temporarily[15]. Authorities also considered using U.S. military bases in Japan and South Korea, because the capacity at bases in Qatar, Bahrain, and Germany, which were being used to temporarily house evacuees, was approaching its limit[16]. Ultimately these facilities were not used, but in a Taiwan contingency the U.S. military bases in Japan and South Korea would be the main evacuation sites. The U.S. used U.S. military bases because the targets of the Afghanistan NEO was mainly U.S. citizens, as well as Afghans who had long worked with the U.S. military and their families. However, in a Taiwan NEO it is difficult to imagine that a large number of foreign evacuees would be temporarily housed at the U.S. military bases in Japan, apart from the 10,000 U.S. citizens. In light of this, the Japanese government itself needs prepare to host large numbers of nationals from third countries, including by coordinating the use of airports and harbors managed by local governments and the private sector, as well as planning and preparing facilities for the temporary evacuees[17].

In any event, an important point in dealing with such a large number of NEOs is to evacuate as many people as possible while keeping civilian aircraft operable, and to do that accurate information processing is essential. This was also pointed out in the case of Afghanistan.

5.How should Japan prepare?

Finally, I would like to examine the issues that need to be considered in Japan’s response to a Taiwan crisis, and pose some questions regarding their resolution.

1) Obstacles to declaring a situation

A key factor in declaring a “important influence situation” or a “survival-threatening situation” will be the presence or absence of countries other than the U.S. that are helping Taiwan. However, China’s crackdown on democratic protests in Hong Kong has raised international alarm over Chinese hegemony, and the U.K., France and Canada have dispatched naval forces to the South China Sea as a part of the U.S.’ freedom of navigation operations. Germany has expressed its intent to do the same. However, these commitments do not necessarily mean these countries will coordinate with the U.S. if the situation deteriorates into a direct armed conflict with China, as Germany and France did not participate in the Iraq War in 2003. While there are high hopes for AUKUS, the degree to which member countries will commit themselves in a Taiwan contingency remains unknown. Hypothetically, if no country other than the U.S. is willing to support Taiwan, and if Japan is the only one to aid the U.S. in opposing China, confusion over declaring a contingency is inevitable. In addition to the fact that neither a “important influence situation” nor a “survival-threatening situation” has ever been declared before, confusion in domestic debate will likely make it even more difficult for the government to make quick decisions.

In addition, legally a “survival-threatening situation” is defined as “an attack on another country with a close relationship to Japan.” It could therefore be argued that Taiwan, which does not have formal diplomatic relations with Japan, is neither “close” nor is it a “country.” However, the government has stated that the criteria could cover “countries with which Japan does not have diplomatic relations.”[18] Officials need to prepare a manual that standardizes contingency procedures in line with this government view.

Furthermore, in the case that an “armed attack situation” was declared and the SDF was deployed in response to an attack by China, the SDF forces in the field would only be able to fight back using weapons under police authority, which could result in an enormous disadvantage. For this reason, a deployment order must be issued at an earlier stage so the SDF can immediately invoke the right of self-defense (the use of force) to fight back in the event of an attack.

2) Urgent issues for quick and accurate decision-making

In times of national emergency, timely and accurate decision-making is critical. In the current response to the COVID-19 pandemic various issues have emerged regarding the timing of declaring a state of emergency. This common problem of “decision-making” was also noted in the September 2010 collision of a Chinese fishing boat with an SDF patrol boat, and in the 2011 Great East Japan Earthquake. The speed of decision-making in “situational awareness” and NEOs, which were addressed in this article, is extremely important. In the COVID-19 response, there have been not only decision-making issues, but also contingency response problems, such as establishing waiting areas for people with minor infections. The problems revealed by these precedents must be examined in detail later so these substantial problems can be resolved.

Usually, the success or failure of decision-making lies in information. Although decision makers often seek more information, it is important to sort out the information that is essential for decision-making and that which can be used for reference. Without this process decision-making will be prolonged because of the confusion caused by a flood of information. This was also the case in the transportation of Japanese nationals and others in Afghanistan, where more than 500 Afghans who had worked with Japan for many years lost the chance to evacuate because of delays in decision-making caused by inadequate information processing, a failure that has come under strong domestic criticism in Japan. Sharing these preparations from the Prime Minister’s Office to the people in the field will enable those on the ground to know the reporting priority, which will in turn lead to quicker decision-making.

Most importantly, even if procedures and manuals are prepared and information is obtained, decision-making is not something that can happen suddenly if one is not familiar with the process. Therefore, it is necessary to establish decision-making mechanisms and conduct exercises at all levels, from in-the-field where personnel directly deal with a contingency to the Prime Minister’s Office where final decisions are made.



  1. 1 Yew Lun Tian, Yimou Lee, “China drops word 'peaceful' in latest push for Taiwan 'reunification',” Reuters, May 22, 2020.
  2. 2 “Secretary Antony J. Blinken with Wolf Blitzer of CNN’s The Situation Room,” Interview, U.S. Department of State, February 8, 2021.
  3. 3 Brad Lendon, “Chinese threat to Taiwan 'closer to us than most think,' top US admiral says,” CNN, March 25, 2021.
  4. 4 Statement of Admiral Philip S. Davidson, U.S. Navy Commander, U.S. Indo-Pacific Command Before the Senate Armed Services Committee on U.S. Indo-Pacific Command Posture, U.S. Senate Committee on Armed Service, March 9, 2021,pp.32-37.Hiroyuki Akita, “Future balance of power haunts US as China bulks up,” Nikkei Asia, March 16, 2021.
  5. 5 「重要影響事態に際して我が国の平和及び安全を確保するための措置に関する法律」。(Japanese)
  6. 6 内閣官房 「平和安全法制等の整備について」(2021年5月22日アクセス)(Japanese)
  7. 7 「重要影響事態法」第8条及び第9条。(Japanese)
  8. 8 Ibid.
  9. 9 自衛隊法第95条の2(合衆国軍隊等の部隊等の武器等の防護のための武器の使用)。 (Japanese)
  10. 10 Article 76, Paragraph 1, Item 1 of the SDF Law allows for the mobilization of defense forces not only "in the event of an armed attack from outside," but also in situations where there is an "imminent danger of such an attack.” Therefore, even if a "defense deployment" is ordered, it does not mean that the SDF will use force if there has not been an armed attack. In addition, even if an armed attack occurs and a defense mobilization is issued, the SDF cannot use force until there is a separate order to use force (Article 76 of the SDF Law only stipulates the prime minister's authority to order a defense mobilization, and there is no specific provision on the procedure to order "activation of the right of self-defense" (use of force by the SDF). Therefore, this authority is included in the authority of the Prime Minister under Article 76.)
  11. 11 自衛隊法第84条の三。(Japanese)
  12. 12 Ibid., 84-4.
  13. 13 Ministry of Defense, 2021 Defense of Japan, p.299.
  14. 14 「臺灣地區現持有效居留證(在臺)外僑統計(按國籍及職業分)」中華民国内政部移民署『外僑居留人數統計表11007』2021年7月31日。(Chinese)
  15. 15 Ned Price, “Department Press Briefing,” U.S. Department of State, August 20, 2021.
  16. 16 Hyonhee Shin, “U.S. scraps plan to use S.Korea, Japan bases for Afghan refugees -sources,” Reuters, August 24, 2021.
  17. 17 「重要影響事態法」第8条及び第9条。(Japanese)
  18. 18 「水野賢一参議院議員の質問に対する政府答弁書」内閣参質189第202号、2015年7月21日。 (Japanese)