Research

Constrained Peace: Rethinking China’s Rise and the Future of the East Asian Security

The book argues that the Indo-Pacific’s relative stability in the face of China’s rise is best explained by a set of dual constraints that limit both China’s ability to coerce its neighbors and those neighbors’ willingness to pursue rapid military buildup. Material factors such as geography, regional power balances, and the high costs of territorial conquest sharply restrict China’s capacity for large-scale aggression, while China’s historically shaped status-seeking further narrows its territorial ambitions. As a result, Beijing relies on gray zone tactics and nontraditional tools of influence rather than overt military force. These calibrated forms of pressure heighten regional anxiety but do not generate the clear, immediate threats needed to justify full-scale arms racing, leading Indo-Pacific states to adopt measured responses that blend modest defense increases with economic and diplomatic countermeasures. The book concludes that peace in East Asia rests on enduring structural limits that make strategic restraint both possible and rational for China and its neighbors alike.

“The Bargaining Theory of War and North Korea.” (First author, with David C. Kang)  Asian Journal of Peacebuilding, Vol 13, No 1 (2025), pp. 19-40. Link

“The Threat of China’s Rise Reconsidered.”

• Recipient of the Best Graduate Student Paper Award at the American Political Science Association (2024).

China’s rise has led many scholars to argue that it poses a growing threat in East Asia, raising concerns that the region’s ongoing military buildup could escalate into a destabilizing arms race. The possibility of a weakened U.S. security commitment further amplifies these concerns. If the threat level in East Asia is indeed high, intense arming and drastic countermeasures in response to a reduced U.S. presence may follow. However, if the threat is more moderate, such outcomes may be less likely than widely assumed. Despite its centrality in regional security debates, the actual level of threat China poses has received limited systematic analysis. This paper addresses that gap by evaluating China’s threat based on its material capabilities and revisionist intentions. The findings challenge prevailing narratives, suggesting that China’s threat to its neighbors is less severe than commonly portrayed. This helps explain why East Asian states have pursued relatively moderate military buildups. Consequently, the likelihood of a full-scale arms race or severe repercussions from a declining U.S. presence may be overstated.

“Evaluating the East Asian “Arms Races”: Three Layered Analysis.”

In recent years, it has often been claimed that there is an ongoing arms race between China and East Asian states. Is this truly the case? How do we know if the trend of military buildup in East Asia constitutes an arms race, which is believed to increase the likelihood of war? Scholars are divided on this issue, often reaching different conclusions based on varying indicators and criteria for what constitutes an arms race. This paper offers a thorough review of the “East Asian arms race” case by combining both quantitative and qualitative measurements. Three layers of analysis are used: first, applying existing quantitative criteria for arms races; second, comparing the degree of military buildup in East Asia with that of states outside the region; and third, conducting qualitative case studies. By examining the trend of military buildup in East Asia through these analyses, this paper argues that current levels of arming in the region are more of a “routine” arms competition and unlikely to be an arms race.

“The Military That Isn’t: How Legalized Anti-Militarism Shapes the Limits of Japan’s Defense Policy“

Scholarship increasingly claims that Japan’s anti‑militarism has eroded, pointing to rising defense spending, expanding SDF missions, and new counterstrike capabilities. This paper challenges that view by highlighting a neglected but enduring dimension of anti‑militarism: its legalization. Because the Self‑Defense Forces (SDF) are legally defined as an administrative organ rather than a military, they operate under a police‑like system that imposes significant operational constraints. In peacetime, the SDF may act only under narrowly defined regulations governing permissible uses of weapons, and any shift to military operations requires explicit political authorization. The absence of military law and courts further complicates discipline and morale. These constraints hinder crisis response, coordination with allies, and the credibility of Japan’s defense posture. Drawing on underutilized Japanese‑language sources, the study shows how domestic legislation continues to institutionalize restraint. The findings have important implications for Japan’s ability to respond to regional contingencies and for effective alliance coordination.

“Peaceful Rise or Security Competition? Rising Powers, Uncertainty, and the Costs of Territorial Expansion”

Is security competition between rising powers and their neighbors inevitable? Conventional wisdom is that rising powers’ capabilities should, more or less, have a positive correlation with their neighbors’ military efforts. Since potential adversaries’ intentions are often difficult to discern, rising powers’ neighbors should increase their military efforts to catch up with the rising powers’ increasing capabilities to prepare for a contingency. However, this paper argues that existing studies overlook another inadvertent effect of increasing capabilities, which is that the increase in rising powers’ capabilities can, counterintuitively, update their neighbors’ belief in a way that rising powers are more likely to be status quo powers. Therefore, the increasing capabilities of rising powers have mixed effects on their neighbors’ military efforts. This paper discusses the response of East Asian states to China’s rise and Eastern European states to resurgent Russia to illustrate the plausibility of my argument.

“Countering Threat, Placating Friends: Explaining Japan’s Asymmetric Defense Policy“

Strengthening defense capabilities is costly. At the same time, states needs to counter external threats and also placate allies and partners that they are sharing a fair burden of maintaining peace. How do states prioritize their defense policy in such constraints? This paper argues that under political and financial constraints, states prioritize defense policies that can fulfill two functions at the same time over ones that play one either of them. The first function is to increase their defense capabilities, and the second is to “signal” to their allies and partners that they are sharing the burden. This paper uses Japan’s recent defense buildup to illustrate the logic. In 2022, Japan made substantial changes in its traditional defense policy in two ways. First, it decided to increase its defense-related spending to well beyond the traditional 1% of the GDP, and second, it would procure offensive weapons, such as cruise missiles that can attack the territory of other states. However, the legal restrictions on the Self-Defense Force that have long been deemed as hindering the SDF’s effective operations were not changed. Both defense spending and weapons procurements can not only improve Japan’s capabilities but also have significant signaling value to its allies because they are conspicuous. Meanwhile, although lifting the legal restrictions can improve Japan’s capabilities, it has little signaling value to its allies because such legal restrictions are little known outside Japan. The difference in the “signaling” value can explain why Japan prioritized defense spending and weapons acquisitions over lifting legal restrictions.

Works in Progress

“Revisiting ‘War of Miscalculation’ in East Asia.”

“Hope for the Best, Plan for the Mediocre: What Worst Case Scenario?”

“Militarize or Professionalize? East Asia’s Strategic Choice in the Maritime Gray Zone“