RESOLVED: Japan Should Deepen Defense/Security Cooperation with Taiwan

Debating Japan Vol. 3 Issue 3


From the Editor

Japan faces a complex situation concerning its relationship with Taiwan. Japan’s “One-China” policy recognizes the government of the People’s Republic of China as the sole legal government of China and maintains Japan-Taiwan relations as a working relationship on a non-governmental basis. However, Japan’s unofficial engagement with Taiwan has flourished in recent years across a range of issue areas. In the face of Chinese coercion in the East China Sea, should Japan be doing more with Taiwan on defense/security cooperation?

In the fourteenth issue of the Debating Japan newsletter series, the CSIS Japan Chair invited Grant Newsham, research fellow with the Japan Forum for Strategic Studies, and Mr. Benjamin Self, vice president of the Maureen and Mike Mansfield Foundation, to share their perspectives on Japan-Taiwan defense cooperation.


Mr. Grant Newsham
Research Fellow, Japan Forum for Strategic Studies

“Taiwan’s defense is Japan’s defense.”

Look at a map, and it’s hard to think otherwise. And Beijing would agree.

The People’s Republic of China (PRC) has said it will take Taiwan—and by force if necessary. Take Beijing at its word. But that doesn’t mean it will succeed. Not if the price is too high, and the certainty of U.S. and Japanese military involvement on Taiwan’s behalf puts things into the ‘too expensive’ category.
Tokyo either helps Taipei defend itself or sits by and hopes Taiwan doesn’t come under Chinese control. If it’s the latter option, Japan had better prepare to give Beijing a near veto over its military, political, economic, and even domestic policies. And Japan just might need to relinquish parts of its southern territory, starting with the Senkaku Islands.

Why so dire?

Taiwan occupies strategic geography, sitting in the middle of the sea-lanes through which much of Japan’s energy supplies and trade flow. Take Taiwan, and China can cut these whenever it wants.

Forget about “going around” the South China Sea. A PRC-controlled Taiwan will be a springboard for the People’s Liberation Army (PLA) naval and air operations into the heart of the central Pacific.  

And Japan’s southern defenses in the southwest island chain (Nansei Shoto) are outflanked. Expect increased pressure in the East China Sea—and the Senkakus—and eventually a push to take the Ryukyus.

And the knock-on effects are just as frightening.

Japan will only operate in Southeast Asia and elsewhere at Beijing’s sufferance. Japan’s regional influence will wane as partners draw back under Chinese pressure. 

Even worse, the loss of Taiwan will deliver a body blow to the United States’ position and prestige in Asia. Smaller regional nations will scramble to cut the best deal possible with the PRC. That is bad news for a Japan that relies on the United States to underwrite its defense. 

The days when Tokyo could rely on the United States to “take care of” Taiwan are over, and Taiwan cannot survive on its own. The United States is overstretched and needs the help Japan can provide with Taiwan. Indeed, the more Japan does to assist, the more likely it is that the United States will defend Japan. 

With the Americans gone or staggered after Taiwan falls, Japan will face the near-impossible task of building up the Japanese Self-Defense Forces to handle the PLA—and will need to “go nuclear.” 

But won’t Japan’s public oppose military ties with Taiwan? Nagatacho might be surprised. Opinion polls routinely show large majorities with negative opinions of the PRC and its behavior. Japan’s public understands national security better than politicians.

Still, one can hear the excuses for doing nothing:

Can’t Japan just let Taiwan go and cut a deal with China? It can. But Beijing breaks its promises. And there is not a shred of evidence Beijing will settle for “co-preeminence” in Asia along with Tokyo. It is incapable of regarding the Japanese as equals. Indeed, Chinese policy is as much a desire to put Japan “back in its place” and teach it a lesson for savaging China in the twentieth century, as it is about geopolitics.

And there is the old standby: Certainly, China will not upset its important economic relationship with Japan, will it? Anybody care to take that bet? Economic ties haven’t restrained Chinese behavior much in recent times. Just take the last decade—constant pressure around the Senkakus, a rare earth boycott, periodic “riots on demand” against Japanese companies in China, taking Japanese hostages for political reasons, and non-stop anti-Japan propaganda. (Just watch Chinese TV some evening.)

With Taiwan back in the fold, it will be no holds barred for Beijing against the Japanese “dwarves.” That’s Beijing’s word, not mine. 

The business community may worry about the economic implications of taking this kind of approach. However, in this case, national security concerns should take precedence.

So forget about economic ties leading to peace in our time. More likely true is the adage that: the more willing and ready you are to fight, the less likely you’ll have to. 

Defense ties with Taiwan are a prerequisite.

What will defense cooperation between Tokyo and Taipei look like? Something that breaks Taiwan’s isolation and demonstrates Japan’s support (along with the United States) for Taiwan.

Start by exchanging liaison officers. Working with the United States, cooperate in the humanitarian assistance/disaster relief field, making use of each nations’ amphibious forces. In addition, it’s easy to get the Taiwan Air Force and Japan Air Self-Defense Force (JASDF) together on Guam for joint training. Navies can train anywhere.

Invite Taiwan to participate in Missile Defense activities and North Korean sanctions enforcement operations.

And have JASDF fighters from Okinawa (along with U.S. Air Force aircraft) join the Taiwan Air Force on escort missions when the Chinese PLA Air Force flies around Taiwan looking to intimidate.

Ultimately, this is all about principles. Taiwan is an economically successful model of consensual government and individual liberty, just like Japan. This is anathema to Beijing. It can’t justify the authoritarianism of the Chinese Communist Party (CCP) when there are competing examples of stable Asian nations. For Japan’s own sake, Taiwan is worth defending. If Japan turns away from Taiwan, with eyes primly averted while a free people are enslaved, then Japan will, at the very least, deserve contempt and even might be next. 

Tokyo can bet that the communist dictatorship that wants Taiwan will be coming after it in short order.

Japan still sees itself as the leading nation in Asia. If it is afraid of deepening defense ties with a free Taiwan for fear of Beijing, it might as well step into the back seat and let the CCP drive.
Mr. Benjamin Self
Vice President, The Maureen and Mike Mansfield Foundation

Preservation of Taiwan’s de facto independence is a core security interest of Japan, and China’s ongoing expansion of its military capabilities is threatening the balance of power across the Strait. However, it is nonetheless not wise for Japan to deepen its defense and security relationship with Taiwan. Doing so would, in fact, be counterproductive. Rather than poking the hornets’ nest and inducing an emotional overreaction from a hypersensitive Chinese Communist Party (CCP), Japan should instead respond to China’s efforts to gain coercive leverage by significantly increasing interoperability with the United States, while maintaining current levels of sub rosa contact with Taiwan’s defense establishment.

Chinese Nationalism, Taiwan, and the Japan Factor

The People’s Republic of China (PRC) leadership is highly critical of any international support for the Republic of China’s (ROC) government on Taiwan, and any overt steps by Tokyo to defend Taipei will produce a reflexive and even neuralgic response. Whether it is because the leadership itself holds strong anti-Japanese attitudes or because it has to avoid looking weak against Japan in the eyes of the nation, the CCP will find it necessary to retaliate, punishing Japan at any cost. As the effort to discipline Seoul for deploying THAAD radars shows, Beijing will bear significant pain—economic, political, reputational costs—if they deem it necessary. Just imagine how much more extreme a reaction the sensitive matter of Taiwan would produce.

Some have argued that since China is “pedal to the metal” on military expansion anyway, there’s no need to fear a security dilemma in Northeast Asia by having Japan push back firmly. This understates the degree to which China could still escalate or accelerate its defense buildup. The current levels of increase in defense spending are the result of a political process with a wide variety of factors in balance with each other, but Japan’s direct involvement would rewrite the political calculus within China.

In other words, respecting Beijing’s sensitivity on this issue is not just a matter of diplomacy and does not imply giving the PRC any veto over Japanese government policy. Rather, it reflects an acceptance of the reality that this issue is one of critical national importance to the CCP and its regime stability. While the government of China is capable of declaring matters as “core national interests” in an effort to control how other states address that issue—to cow them into submission in some cases—the concern over Japanese involvement in Taiwan (and thus in Chinese sovereignty) is not a matter of spin.

The U.S.-Japan Alliance and Taiwan’s Security

While any open role for the Japanese Self-Defense Forces (JSDF) in direct support of Taiwan would be extremely provocative, at the same time, it is widely understood that Japan plays an important, if mostly passive, role in Taiwan’s security. Article VI of the Treaty of Mutual Cooperation and Security Between Japan and the United States of America allows the United States to use bases and facilities in Japan for “the maintenance of international peace and security in the Far East.” For 60 years, Japan has supported the defense of Taiwan through this indirect mechanism. More recently, with the 2015 revision to the Guidelines for U.S.-Japan Defense Cooperation, Japan has also taken on a role in asset protection as well as combined efforts in maritime operations and logistics. Each of these aspects has a significant impact on the ability of U.S. forces to operate in the areas surrounding Taiwan.

Where Japan could best contribute to deterring PRC aggression is by continuing to deepen integration between the JSDF and the U.S. military. Enhanced and automated intelligence sharing, improved interoperability for integrated space- and air-defense (including against cruise and ballistic missiles), better undersea domain awareness and coordination, and more robust cybersecurity are all areas where the U.S. and Japanese defense establishments are already making important efforts. These are all areas that have special bearing on the ability of the United States to maintain freedom of action in the possible defense of Taiwan.

At present, Japan avoids sending active-duty military personnel or civilian defense officials to Taiwan but instead relies on informal channels using retired officers and even members of the National Diet to communicate and share perspectives on strategic issues. Defense intellectuals and academics specializing in international affairs or China studies also make frequent visits to the island. Beijing dislikes this, but as long as cooperation remains in this unofficial space, it has been tolerant. Moving toward an open, official defense linkage between Tokyo and Taipei would jeopardize even the current level of relations, forcing an even more stark choice between the ROC and PRC. While the politics of Japan, like those of the United States, might be leaning further against China and friendlier to Taiwan, the political economy of economic interdependence—even for Taiwan itself—makes the notion of deepening Japan-Taiwan defense ties a bad idea.

About the Authors

GRANT NEWSHAM is a retired U.S. Marine Corps officer and a research fellow with the Japan Forum for Strategic Studies in Tokyo.  He served as the U.S. Marine Corps attaché at U.S. Embassy Tokyo and also as the first Marine Corps liaison officer to the Japan Self-Defense Force. He was instrumental in establishing Japan's amphibious force. Mr. Newsham spent 2019 in Taiwan conducting research on improving Taiwan's defense.

BENJAMIN SELF is vice president of the Maureen and Mike Mansfield Foundation. Mr. Self serves as director of the Mike Mansfield Fellowship Program, a congressionally mandated professional exchange for mid-level U.S. government employees. He also manages the U.S.-Japan Network for the Future, a program launched in 2009 to foster a new generation of Japan specialists. In addition to supervising these and other major Foundation programs, Mr. Self provides strategic advice to the Foundation’s president and CEO on the Foundation’s administration, direction, and mission and assists the president in leading the Foundation’s development and fundraising efforts.

Mr. Self previously was the inaugural Takahashi Fellow in Japanese Studies at the Walter H. Shorenstein Asia-Pacific Research Center at Stanford University. From 1998-2008, he was at the Henry L. Stimson Center as a senior associate working on Japanese security policy. While at the Stimson Center, he directed projects on Japan-China relations, fostering security cooperation between the U.S.-Japan Alliance and the PRC, Japan’s nuclear option, and confidence-building measures. Mr. Self has also carried out research and writing in areas such as nuclear non-proliferation and disarmament, ballistic missile defense, Taiwan’s security, Northeast Asian security dynamics, the domestic politics of Japanese defense policy, and Japan’s global security role. From 2003 until 2008, Mr. Self was living in Africa and studying the role of Japan in Africa, including in humanitarian relief, economic development, conflict prevention, and resource extraction. He also has served as an adjunct lecturer at Georgetown University, George Washington University, and American University.



Japan’s Policy Toward China and Taiwan,” Madoka Fukuda (2018)
The Strategic Impact of the Taiwan Issue on the U.S.-Japan Alliance,” Yasuhiro Matsuda (2018)
An Emerging Structure of Japan-China Relations: Constant Maritime Tension and Mutual Cooperation,” Naoko Eto (2018)


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Asia Forecast 2020” (January 22, 2020)
The 26th Annual U.S.-Japan Security Seminar: The U.S.-Japan Alliance at 60” (January 14, 2020)
Strategic Japan: Shaping the Rules Based Order in the Reiwa Era” (January 8, 2020)


Read the 2019 working papers and listen to the podcasts here


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About the Editor

Hannah Fodaleis a research assistant with the Japan Chair at the Center for Strategic and International Studies, where she focuses on projects involving U.S.-Japan relations and security in the Indo-Pacific region.