With the United States repeatedly urging its allies to increase their defense spending to 3.5% of their Gross Domestic Product (GDP) at the Asia Security Summit (Shangri-La Dialogue) in Singapore, attention is focused on the potential impact this will have on Japan's discussions regarding the revision of its three key security documents scheduled for this year.

During his speech at the Asia Security Summit on the 30th (local time), U.S. Secretary of Defense Pete Hegseth reiterated his demand for allied and partner nations to expand their defense spending to 3.5% of GDP. He specifically praised South Korea, which pledged to increase its spending to 3.5% of GDP, stating that it "demonstrated pragmatism and leadership." Secretary Hegseth publicly pressured for arms buildup, even suggesting the possibility of reconsidering relations with countries that are passive about sharing the defense cost burden. The Yomiuri Shimbun reported that while these remarks are aimed at countering China's military expansion, they act as a financial burden for regional countries, including Japan. The Mainichi Shimbun reported that Secretary Hegseth stated that deterring China in the Indo-Pacific region is a core axis of the U.S. defense strategy, expressing his intention to maintain engagement in the region.

The Japanese government is maintaining a cautious stance regarding U.S. pressure. Lawmaker Shinjiro Koizumi, who held a separate meeting with Secretary Hegseth, stated that while the U.S. side mentioned defense spending, there were no discussions based on specific figures or conclusions. He maintained the existing position that "the Japanese government will make its own independent judgment" regarding the demand for an increase, and a high-ranking Japanese government official also drew a line, stating, "We will not increase spending simply because the U.S. is demanding it." However, it has been suggested that the defense spending issue was likely treated as a major agenda item in subsequent bilateral talks.

Meanwhile, the Japanese government is conducting ruling party discussions under the policy of revising the National Security Strategy, the National Defense Strategy, and the Defense Buildup Plan—the so-called three key security documents—within this year. The ruling Liberal Democratic Party (LDP) presented the opinion that the government's plan must clearly state a target for increasing defense spending and has begun internal party discussions. The LDP recently held a security research council meeting and gathered opinions that the scale of additional increases should be considered by referencing examples from North Atlantic Treaty Organization (NATO) member states, South Korea, and Australia.

Domestic challenges regarding securing financial resources also remain. Japan's defense-related budget for the 2026 fiscal year is 10.6 trillion yen, which is about 1.9% of GDP compared to the 2022 fiscal year. Japan achieved its "2% of GDP" target ahead of schedule by formulating a supplementary budget in the 2025 fiscal year. To further increase defense spending, the country must manage potential backlash from neighboring countries and domestic public opinion, while also devising measures to secure financial resources. The LDP has not explicitly stated whether it will raise taxes, but it has presented its position to continue discussions on financial resources, premised on persuading the public.