Turning Point of Japan's Security Strategy under the Trump Administration: The Deployment of Counterstrike Capability and the Deepening of Engagement with Europe

In March 2026, Japan's security policy is at a historic turning point. Just before Prime Minister Sanae Takai meets with President Donald Trump at the White House on March 20, Tokyo has begun deploying domestically developed counterstrike capabilities while simultaneously moving to strengthen its strategic partnership with Europe. This marks one of the boldest transformations in Japan's post-war defense policy.

On March 22, the Ministry of Defense announced the deployment of an improved version of the Type 12 surface-to-ship guided missile at the Kengun Garrison in Kumamoto Prefecture. Originally designed to target enemy vessels approaching Japan, this missile has now gained the capability to attack land targets due to the recent improvements. According to reports from the Indo-Pacific Defense Forum, if launched from the Kengun Garrison, its range could cover much of East Asia, potentially including a wide area of North Korea and parts of the eastern coast of China within its reach.

This deployment is a realization of the new national security strategy adopted by Japan in December 2022. The strategy explicitly states the possession of "counterstrike capability" while maintaining the principle of exclusively defensive defense, allowing for the capability to attack enemy bases such as missile launch sites. For Japan, which has avoided possessing offensive weapons under the constraints of Article 9 of its constitution for over 70 years, this represents a groundbreaking policy shift.

However, behind this military enhancement lies serious concern regarding the Japan-U.S. alliance. In mid-March, President Trump requested allied nations to dispatch naval vessels to lift the blockade of the Strait of Hormuz. When allies refused, Trump posted on social media, "Our military success means we no longer need support from NATO countries. The same goes for Japan, Australia, and South Korea."

In a parliamentary response on March 19, Prime Minister Takai cautiously addressed Trump's comments, stating, "The situation is changing daily, and messages from the U.S. side are also evolving." For Japan, dispatching the Maritime Self-Defense Force to the Strait of Hormuz presents significant constitutional and legal hurdles. After the Gulf War in 1991, Japan sent six minesweepers to the Persian Gulf, but that was more than six months after the U.S. military's Operation Desert Storm had concluded. Prime Minister Takai stated that "minesweeping at the end of a war" is constitutionally permissible, but there are currently no plans to dispatch minesweepers.

The Iran War is delivering a direct economic blow to Japan. As the world's fifth-largest oil importer, Japan relies on the Middle East for 95% of its oil. The blockade of the Strait of Hormuz has disrupted supply, and combined with the depreciation of the yen, import costs have skyrocketed. Japan, which is not directly involved in the war, is facing domestic political issues in the form of rising living costs.

In this context, Japan's strategists are most concerned about the declining commitment of the Trump administration to East Asia. Last week, the Trump administration's sudden relocation of U.S. missiles from South Korea to the Middle East shocked not only Seoul but also Tokyo. "Is President Trump still interested in deterring North Korea? If Beijing takes action against Taiwan, will he act?" asked Kazuto Suzuki, director of the Institute of International Relations in Tokyo, in an interview with Euronews.

For Japan's strategists, stabilizing East Asia, deterring China, and maintaining freedom of navigation in the South China Sea can only be achieved with active and continuous U.S. engagement. Trump's abrupt shift of focus to the Western Hemisphere (with potential implications for Venezuela and Cuba) and the Middle East (Iran) presents a highly troublesome development for Japanese leaders.

Professor Michito Tsuruoka of Keio University’s Keio Strategy Center told Euronews, "Europe is becoming more important to us. We need Europe for stability." In fact, relations between the EU and Japan have reached unprecedented heights in recent years. The Strategic Partnership Agreement (SPA) and the Economic Partnership Agreement (EPA) signed in 2019 created one of the world's largest economic zones. Furthermore, in 2024, the EU-Japan Security and Defense Partnership, the first of its kind between the EU and an Asia-Pacific country, will be launched, officially deepening military and intelligence cooperation.

Chatham House analysis points out that Japan, South Korea, and the Philippines are referred to as the "security triangle" by U.S. military commanders. These countries play a crucial role in the U.S. alliance network in the Indo-Pacific region due to their strategic positions and importance in balancing China's influence. However, Trump's focus on the Iran War and erratic demands on allies present common security challenges for these countries while also providing opportunities to seek their own responses.

Prime Minister Takai intends to leverage the good relationship established with President Trump in October to emphasize Japan's significant new commitments. This includes accelerating the goal of achieving a defense budget of 2% of GDP, participating in Trump's "Golden Dome" missile defense plan, and agreeing to invest $550 billion in the U.S. in exchange for reducing tariffs from 25% to 15% last year.

However, it is unclear whether President Trump will appreciate these efforts. The best-case scenario for Tokyo is a swift conclusion to the Iran War. Former House of Representatives member Motohiro Funada (Chairman of the EU-Japan Parliamentary Alliance) told Euronews, "Considering the current crisis, the relationship between the EU and Japan needs to become stronger. And it will," emphasizing that maintaining the international order is a common important goal.

Japan's move to deploy counterstrike capabilities and deepen relations with Europe is not merely an enhancement of military power. It indicates that Japan, which has relied on the U.S. security umbrella for over 70 years, is facing the uncertainties of the Trump era and is seeking a transition to a more autonomous and multifaceted security strategy. As Professor Hidemasa Inomata of the University of Tokyo points out, the strategic goal is "a reliable, feasible, and democratically compatible joint resilience against coercive actors."

At this historic turning point, Japan is steadily enhancing its defense capabilities while maintaining its alliance with the U.S. and strengthening cooperation with Europe and other democratic nations. The deployment of the improved Type 12 surface-to-ship guided missile is merely a symbolic first step. In the coming years, how far Japan's security policy evolves and the impact it has on the strategic balance in East Asia will attract attention across the region.