Military Exercises Around Taiwan by China and the Miyako Strait: An Analysis of Serious Strategic Threats to Japan's Security

The large-scale military exercises conducted by the People's Liberation Army of China around Taiwan from December 29 to 30, 2024, marked a strategic turning point that significantly impacts the security environment in Northeast Asia, particularly Japan. This article analyzes the multi-layered threats indicated by these exercises from the perspective of Japanese defense experts.

**Strategic Importance of the Miyako Strait and Sino-Russian Cooperation**

On December 9, the joint cruise of Chinese and Russian strategic bombers over the Miyako Strait carries serious implications beyond mere show of force. The Miyako Strait, located between Okinawa Island and Miyako Island, is a crucial breakthrough point in the "first island chain" for the Chinese Navy to access the western Pacific. By passing through this strait, the Chinese military aims to showcase its deployment capabilities from the East China Sea to the Pacific, exposing the vulnerabilities in Japan's defense of the southwestern islands.

The military cooperation between China and Russia clearly indicates a strategic intent that challenges the U.S.-led regional order, rather than just tactical collaboration. This joint action should be viewed as a simulation of the multi-faceted military pressure Japan would face in the event of a crisis in Taiwan.

**Direct Threats to Japan from Exercises Around Taiwan**

China's exercises around Taiwan pose three significant threats to Japan. First, if scenarios of a blockade of the Taiwan Strait or military unification materialize, Japan's maritime traffic routes (sea lanes) would be directly endangered. A large portion of Japan's trade passes through this maritime area, threatening vital economic security interests.

Second, the southwestern islands, such as Yonaguni Island, Ishigaki Island, and Miyako Island, are extremely close to Taiwan, meaning that a crisis in Taiwan would immediately impact Japanese territory and airspace. Missile launches and naval deployments during the exercises increase the risk of accidental or intentional attacks on these islands.

Third, U.S. military bases in Japan are likely to be considered important targets in China's operational plans. Given that Japanese bases would serve as rear support bases for Taiwan's defense, Japan risks automatically becoming a party to the conflict.

**JSDF's Response Capabilities and Challenges**

The joint exercise conducted on December 10 between the Japan Air Self-Defense Force's F-35s and U.S. B-52 strategic bombers was a responsive countermeasure to Sino-Russian provocations. While this rapid response demonstrates the effectiveness of the Japan-U.S. alliance, it also highlights the structural challenges faced by the Self-Defense Forces.

Although progress has been made in strengthening the defense of the southwestern islands, there remain many areas needing improvement, such as ammunition stockpiles, the density of missile defense system deployments, and the vulnerability of inter-island logistics networks. In particular, doubts remain about operational continuity in scenarios of long-term maritime blockade or loss of air superiority.

Additionally, the legal constraints on the Self-Defense Forces and the slow decision-making process could lead to fatal delays in response to rapidly evolving crises. While the possession of enemy base attack capabilities (counterstrike capabilities) has been decided, the operational standards and political decision-making mechanisms remain unclear.

**The Necessity of the Japan-U.S. Alliance and the Need for Deepening**

In the face of China's military rise, Japan's deterrence alone is not realistic. The Japan-U.S. alliance is the cornerstone of Japan's security policy, and its deepening and enhancement of effectiveness are urgent tasks.

It is crucial to maintain the reliability of the U.S. "extended deterrence," particularly the nuclear umbrella, while enhancing interoperability in conventional forces. Joint operations of F-35s, strengthening information sharing, and increasing the frequency of joint training will send a clear deterrent message to China.

However, Japan must break free from excessive dependence on the U.S. and substantially strengthen its own defense capabilities. Increasing defense spending to 2% of GDP, building capabilities in cyber and space domains, and strengthening the defense industrial base are pressing issues.

**Conclusion: A Time for Resolve and Preparation**

The intensification of China's exercises around Taiwan and activities in the Miyako Strait signifies the complete end of the era of "peace dividends" for Japan. We are now facing the most severe security environment since the post-war period.

The Japanese government and its citizens must confront the reality that a crisis in Taiwan directly translates to a crisis in Japan, and they must urgently expedite necessary legal reforms, budget allocations, and the formation of national consensus. A commitment to strengthening deterrence and diplomatic efforts as two wheels of the same vehicle is required to maintain peace and stability in the region.