As the United States continues to urge its major Asian allies to increase their defense budgets, discussions on expanding Japan's defense spending are expected to gain momentum ahead of its security strategy revision scheduled for this year. In particular, the target of "3.5% of GDP" presented by the U.S. is acting as a significant variable in Japan's security policy.

U.S. Demands for a Significant Defense Spending Hike According to Japanese media and diplomatic and security sources, the U.S. strongly raised the need for its allies to increase their defense budgets on the sidelines of the recent Asia Security Summit (Shangri-La Dialogue) held in Singapore. In his speech, U.S. Secretary of Defense Pete Hegseth emphasized that allies and partner nations must expand their defense spending to 3.5% of their Gross Domestic Product (GDP).

Secretary Hegseth positively evaluated South Korea, which has already announced plans to increase its defense budget, and called for other allies to take on more active roles. He reportedly reiterated that the U.S. cannot bear the security burden alone and requested tangible military buildups, including the acquisition of warships and submarines.

Revision of Japan's 'Three Core Security Documents' and Defense Budget These remarks from the U.S. are placing considerable pressure on the Japanese government, which is pushing to revise its security strategy within the year. Currently, the Japanese government is reviewing the revision of the so-called "three core security documents": the National Security Strategy, the National Defense Strategy, and the Defense Buildup Plan. Within the ruling Liberal Democratic Party (LDP), there are also calls for the need for additional increases in defense spending.

Japan's defense-related budget for the 2026 fiscal year is approximately 10.6 trillion yen, which accounts for about 1.9% of its GDP. Although this figure has steadily increased over the past few years, it still falls short of the 3.5% level demanded by the U.S.

Defense Minister Koizumi: "A Matter for Our Own Judgment" However, the Japanese government maintains its stance that it will not unilaterally increase its defense spending simply to comply with U.S. demands. Following his meeting with Secretary Hegseth, Defense Minister Shinjiro Koizumi explained, "It is true that the U.S. side mentioned the defense spending issue, but there were no discussions demanding a specific amount or target." Emphasizing that increasing the defense budget is "a matter for Japan to decide on its own," he reaffirmed the government's existing position.

Checking China and Indo-Pacific Security Cooperation Looming in the background of these discussions is China's military expansion. The U.S. has recently designated China's naval buildup and its expanded activities in the South China Sea and East China Sea as major security threats, continuously demanding that its Indo-Pacific allies, including Japan, expand their roles.

In response, Japan is accelerating its efforts to strengthen its defense capabilities. During this Shangri-La Dialogue, Defense Minister Koizumi held a series of meetings with Australia, New Zealand, the Philippines, and Singapore to bolster security cooperation. He discussed plans to expand joint exercises and interoperability with Australia and New Zealand, and negotiated the transfer of Maritime Self-Defense Force equipment with the Philippines.

In particular, as the Japanese government shifts its policy toward relaxing weapon export regulations through the revision of the Three Principles on Transfer of Defense Equipment and Technology, there is growing speculation that the soon-to-be-retired Abukuma-class destroyer of the Maritime Self-Defense Force could become the first full-fledged case of lethal weapon exports. The U.S. has also publicly expressed its support for Japan's moves to strengthen its defense capabilities and expand defense industry cooperation.

Secretary Hegseth emphasized to the Japanese side that the U.S. Indo-Pacific strategy will not waver, reaffirming the U.S. commitment to strengthening cooperation with Japan to keep China in check. Experts analyze that this U.S. demand for increased defense spending goes beyond a mere budgetary issue and is directly linked to the restructuring of the Indo-Pacific security order. Attention is now focused on how much Japan will raise its defense spending targets through its security document revisions and how it will push forward its defense export and military expansion policies, as these factors are emerging as key variables in the Northeast Asian security environment.