The Japanese Maritime Self-Defense Force (JMSDF) destroyer Sazanami passed through the Taiwan Strait on Wednesday. This marks the first time a modern Japanese warship has navigated these sensitive waters, which have become a focal point of international geopolitical tension. The passage took place en route to multinational naval exercises, underscoring Japan’s growing involvement in the region’s security dynamics and signaling its willingness to assert itself amid rising tensions with China.
The Taiwan Strait, which separates mainland China from the island of Taiwan, is a key international shipping lane but also a hotspot for military posturing, particularly between the U.S. and its allies on one side and China on the other. China has long considered the strait part of its territorial waters, while other nations, including Japan and the United States, argue that it is an international waterway where freedom of navigation must be maintained.
Sazanami’s passage aligns Japan with other Western democracies, especially the U.S., which have recently increased their presence in the Indo-Pacific to counter China’s growing assertiveness. Japan’s decision is also part of a broader shift in its military posture, as it navigates the complex waters of maintaining security while adhering to its pacifist post-war constitution.
Japan’s Growing Role in Regional Security
Japan’s transit through the Taiwan Strait comes at a time of heightened regional tensions, driven largely by China’s expanding influence and territorial claims in the South and East China Seas. Over the past decade, China has rapidly expanded its military presence in the region, building artificial islands, militarizing existing ones, and sending aircraft carriers and other naval assets into disputed waters.
Traditionally, Japan has maintained a cautious approach toward military engagements, a result of its pacifist constitution adopted after World War II. The document, particularly Article 9, renounces the use of force as a means of settling international disputes. However, as China’s military capabilities grow and its foreign policy becomes increasingly assertive, Japan has gradually shifted towards a more proactive stance on defense.
The deployment of the Sazanami in such a politically sensitive region reflects Japan’s evolving military strategy. Tokyo has been strengthening its self-defense capabilities, modernizing its naval and air forces, and forging deeper security ties with allies, notably the United States, Australia, and South Korea.
Japan’s Defense Ministry has not yet issued a formal statement on the Sazanami’s transit. However, its move can be interpreted as both a show of solidarity with allies, such as the U.S. and Australia, and a signal of support for Taiwan, which faces increasing pressure from Beijing. The choice to navigate the Taiwan Strait at this moment reflects Japan’s desire to assert its role in the regional security architecture and stand up to Chinese provocations.
Multi-National Effort: Australia and New Zealand
The Sazanami was not alone in its passage through the Taiwan Strait. Reports suggest that Australian and New Zealand vessels also transited the waterway, joining the destroyer as part of a multinational naval exercise designed to promote freedom of navigation in the region. The involvement of these two nations signals a broader international consensus against China’s territorial claims and a united front among Indo-Pacific democracies.
Australia and New Zealand, both members of the Five Eyes intelligence alliance and key partners in the region, have become more vocal in their opposition to China’s actions in the South China Sea and the Taiwan Strait. In recent years, Australia, in particular, has taken a harder stance on Beijing’s political and economic coercion, while New Zealand has also shown a willingness to stand with its partners in upholding international law and order.
Their joint participation in this operation with Japan highlights the deepening security ties among U.S. allies in the Indo-Pacific, driven by shared concerns over China’s growing influence and assertiveness. This marks another chapter in the larger shift towards an Indo-Pacific security network that seeks to counterbalance China’s ambitions.
Predictably, China has voiced its opposition to the passage of foreign warships through the Taiwan Strait. Beijing considers Taiwan to be a breakaway province and views the strait as part of its territorial waters. Any foreign military presence in the area is seen as a direct challenge to its sovereignty. This has been particularly true of naval transits by nations that China views as adversaries or rivals.
China’s Ministry of Foreign Affairs reiterated its stance that foreign military activity in the strait threatens peace and stability in the region. In a statement following the Sazanami’s passage, Chinese officials called the move “provocative” and warned that it could lead to increased tensions. However, Beijing stopped short of announcing any specific countermeasures, instead reaffirming its commitment to defending what it sees as its territorial integrity.
China’s increasing military assertiveness has not gone unnoticed by its neighbors. On the same day as the Sazanami’s passage, China conducted a high-profile test of its newest intercontinental ballistic missile (ICBM), a launch that took place without prior notification to Japan. This missile test, the first of its kind in decades, has been interpreted by analysts as a show of strength and a reminder of China’s growing military capabilities. Japan’s Ministry of Defense expressed concern over the test, which coincided with other Chinese military maneuvers in the region, including the movement of a People’s Liberation Army Navy (PLAN) aircraft carrier through waters near Japan’s southern islands.
Shifting Japan’s Post-War Pacifism: A New Era of Defense?
The Sazanami’s passage through the Taiwan Strait represents more than just a routine military operation. It marks a significant turning point in Japan’s approach to defense and security. For decades, Japan has followed a policy of strict pacifism, focusing on defense and relying heavily on its alliance with the United States for security guarantees.
However, under the leadership of Prime Minister Fumio Kishida and his predecessors, Japan has taken steps to expand its defense capabilities. Kishida, who is expected to leave office soon, has overseen a period of increased military spending, the acquisition of new defense systems, and closer cooperation with Japan’s allies.
The decision to send the Sazanami through the Taiwan Strait would have been nearly unimaginable a decade ago, but as China’s assertiveness has grown, so too has Japan’s resolve to defend its interests and maintain stability in the region. This is part of a broader trend in Japanese politics, where national defense is being re-evaluated in light of shifting regional dynamics. The government has increasingly emphasized the need to strengthen Japan’s self-defense forces and has pushed for revisions to the country’s post-war pacifist constitution.
While the move may raise concerns domestically among those who continue to value Japan’s pacifist tradition, it reflects a broader consensus within the Japanese government that more needs to be done to address the growing security challenges posed by China.
U.S. Factor: Strengthening Alliances in the Indo-Pacific
Japan’s actions in the Taiwan Strait come as part of a broader effort by the United States and its allies to counter China’s growing influence in the Indo-Pacific region. At the United Nations General Assembly in New York this week, U.S. President Joe Biden emphasized the importance of strong trilateral relationships between the U.S., Japan, and South Korea as a foundation for ensuring a “free, open, secure, and peaceful Indo-Pacific.”
Biden’s remarks reflect the central role that alliances play in the U.S. strategy to counterbalance China. Over the past several years, Washington has worked to deepen its security ties with Tokyo and Seoul, despite historical tensions between the two East Asian neighbors. The trilateral relationship has become a key pillar of U.S. strategy in the region, particularly as it seeks to address security concerns related to North Korea, the South China Sea, and Taiwan.
In addition to military cooperation, the U.S. has emphasized economic partnerships, technological collaboration, and diplomatic efforts to present a united front against China’s regional ambitions. The passage of the Sazanami through the Taiwan Strait, alongside Australian and New Zealand vessels, is a clear demonstration of this united front in action.
What Comes Next for Japan and the Indo-Pacific?
As Japan navigates a path between its post-war pacifism and the growing need for a robust defense policy, the passage of the Sazanami through the Taiwan Strait will likely be seen as a watershed moment. It signals a new era in Japan’s approach to regional security and a willingness to take a more proactive role in countering threats to the rules-based international order.
For China, Japan’s move is another challenge to its efforts to assert control over the Taiwan Strait and the broader Indo-Pacific region. While Beijing is unlikely to escalate the situation immediately, the ongoing naval presence of U.S. and allied warships in the region will remain a source of friction.
As the geopolitical landscape in the Indo-Pacific continues to evolve, Japan’s actions this week are a reminder that the region’s security dynamics are shifting rapidly. The question now is how these changes will play out in the coming months and years, particularly as Japan, the United States, and their allies continue to push back against China’s growing assertiveness.
