The International House of Japan (Minato-ku, Tokyo; Chairman: James Kondo) – Asia Pacific Initiative (API), in partnership with the East Asia Institute (EAI) of South Korea and the Korea Economic Institute (KEI) in the United States, has conducted the First Japan–U.S.–Korea Public Perception Survey (hereinafter “the survey”).

This year marks the 60th anniversary of the normalization of diplomatic relations between Japan and South Korea, an important milestone for reflecting on the current state and future of bilateral ties. Attention is also focused on the Trump administration’s approach to Japan and South Korea, two key allies in Asia.

The survey was designed to analyze mutual perceptions and attitudes toward key issues among citizens of the three countries, which together form the foundation of increasingly vital trilateral cooperation. It also aims to shed light on public opinion in Japan and South Korea and provide insights for policymakers.

Preliminary findings indicate that while the United States is positioned as an “extremely important ally,” approximately 45% of respondents believe Japan–U.S. relations will “deteriorate,” citing distrust of President Trump (70% hold a negative impression) and opposition to tariff policies. Regarding South Korea, although negative impressions predominate due to historical issues, popular culture such as K-POP and K-dramas contributed to some improvement in its image, and more than half of respondents considered Japan–South Korea relations “important.” Regarding a potential Taiwan contingency, 42% viewed it as “realistic,” highlighting public divisions over how to respond, with opinions evenly split between “logistical support” and “non-intervention.” Furthermore, trust in the U.S. “nuclear umbrella” stood at only 33%, with 49% responding that it was insufficient. At the same time, 63% opposed Japan acquiring its own nuclear weapons, highlighting public unease over nuclear deterrence as well as strong rejection of nuclear armament.

Please refer to the attached document for details.

Comparative data for the three countries will be published on the EAI website (in Korean) at 2:00 p.m. on August 28, and on the KEI website (in English) on August 29. The final analysis results are scheduled for release in October 2025.

Survey Period
August 19–21, 2025 (online survey)

Number of Responses
4,122 total (Japan: 1,037; U.S.: 1,500; South Korea: 1,585)
Survey Overview
Questions were organized into the following five categories, allowing for comparison with past surveys as well as international analysis:
1.Bilateral Relations – Impressions of the U.S. and South Korea, assessment of the importance of relations, and perceptions of political leaders in each country
2.Economy & Trade – Economic relations between Japan–U.S. and Japan–South Korea, free trade systems, and attitudes toward accepting foreign nationals
3.Security – U.S. Forces in Japan, defense cost-sharing, and perceptions regarding the Taiwan Strait and North Korea
4.Culture & History – Interests in U.S. and South Korean popular culture, historical issues, and evaluation of statement on the 80th anniversary of the end of the war
5.Trilateral Cooperation – Japan–U.S.–South Korea security cooperation, information sharing, joint training, and policy responses to a potential Taiwan contingency

API conducted the first Japan–U.S.–Korea Public Perception Survey in collaboration with EAI and KEI. This preliminary report summarizes the findings from the survey of 1,037 respondents in Japan. The survey highlights the candid views of the Japanese public on a wide range of topics, including perceptions of Japan–U.S. and Japan–South Korea relations, security perspectives regarding a potential Taiwan contingency and the North Korean threat, evaluations of economic and trade issues, attitudes toward accepting foreign nationals, and views on the pros and cons of nuclear armament. Key findings are presented below.

1. Impressions of the United States and Japan–U.S. Relations

• 40.5% of respondents had a “favorable impression” of the United States, while 34.5% had an “unfavorable impression,” showing a narrow margin. Reasons for favorable impressions included “an important partner for Japan’s security” (31.0%) and “exercises leadership in the international community” (16.0%). The most common reasons for unfavorable impressions were “a negative impression of the U.S. president” (41.2%) and “strong nationalism” (28.9%).
• Regarding the incumbent President Trump, only 14.7% expressed a “favorable impression,” while 70.1% reported an “unfavorable impression.” Furthermore, concerning the tariffs imposed by the second Trump administration (on automobiles, steel, aluminum, etc.), only 7.5% approved while 76.5% disapproved, indicating overwhelmingly negative sentiment.
• As for the Japan–U.S. relationship itself, 42.4% of respondents described it as “good,” while 34.9% described it as “bad.” On the other hand, 85.9% of respondents said that the Japan–U.S. relationship is “important” for Japan, with only 6.1% giving a negative response. However, regarding future prospects, 44.7% answered that “the relationship will deteriorate,” significantly exceeding the 23.6% who answered that it “will improve,” highlighting strong public anxiety about the future.

2. Impressions of South Korea and Japan–South Korea Relations

• Only 24.8% of respondents held a “favorable impression” of South Korea, while 51.0% held an “unfavorable impression.” Reasons for favorable impressions included “attraction to Korean culture (films, music, sports)” (33.5%) and “attractiveness as a travel destination” (19.1%). The main reasons for unfavorable impressions were “conflict over historical perception (comfort women/forced labor issues)” (28.4%), “reports of anti-Japan demonstrations and statements” (27.0%), and the “Takeshima territorial dispute” (12.1%).
• Regarding current Japan–South Korea relations, 31.8% described them as “good,” while 40.7% described them as “bad.” However, 54.1% responded that Japan–South Korea relations are “important” for Japan, while 30.2% said they are “not important.” Reasons for considering the relationship important included “necessary security cooperation” (39.8%) and “geographical and cultural ties” (33.7%). Conversely, reasons for considering it unimportant included “stagnation on historical issues making strengthened relations difficult” (26.8%) and “differences in values” (20.4%).
• Looking ahead to the next 3–5 years, “no change” was the most common response at 44.9%, while opinions were divided between “improvement” (26.2%) and “deterioration” (28.8%). Regarding priority goals for future Japan–South Korea relations, “restoring/building mutual trust” (23.3%) was most frequently cited, followed by “addressing North Korea’s nuclear issue” (16.6%) and “resolving historical issues” (13.1%). Furthermore, 76.3% answered that the Takeshima issue is “important for Japan–South Korea relations,” confirming it remains a significant challenge.

3. Perceptions Regarding a Taiwan Contingency

• Regarding the possibility of a Taiwan contingency occurring, 42.1% answered “yes,” significantly exceeding the 18.7% who answered “no.” Furthermore, 77.1% stated that it is “important for Japan’s security and economy,” indicating strong recognition of the issue as a major risk to national interests.
• The most serious impact cited was “security risks to the southwest islands (Okinawa/Senkaku)” (28.3%), followed by “economic losses due to disruption of maritime transport routes” (18.3%) and “cessation of semiconductor supplies from Taiwan” (13.4%).
• Regarding the U.S. response, the most common view was that “the U.S. should intervene militarily in coordination with allies” (41.4%). As for Japan’s role, “Japan should limit its role to logistical and humanitarian support” (27.5%) and “Japan should avoid military involvement” (26.0%) received nearly equal support, while only 10.3% responded that “the Self-Defense Forces should participate in frontline combat.”

  On the initial joint response by Japan, the U.S., and South Korea, “diplomatic measures” (36.5%) and “economic sanctions” (24.0%) were the most common answers, while support for “military intervention” remained relatively low at 12.3%.

4. Perceptions Regarding North Korea and Nuclear Deterrence

• Regarding the threat posed by North Korea’s nuclear and missile programs, 42.5% of respondents answered that “information sharing between Japan and South Korea is necessary.” Proactive opinions included “strategic dialogue and policy consultations are needed” (17.8%) and “an alliance should be considered in the future” (12.3%). Conversely, 8.7% opposed security cooperation between Japan and South Korea.
• On the question of whether Japan should possess nuclear weapons independently, 23.7% were “in favor” (strongly in favor: 8.2%, somewhat in favor: 15.5%), while 63.0% were “opposed” (strongly opposed: 43.6%, somewhat opposed: 19.4%), showing overwhelming opposition. Regarding South Korea’s potential nuclear armament, only 15.5% expressed “support,” while 65.0% were “opposed” (strongly opposed: 40.9%).

  Although opposition to Japan’s nuclear armament remains the majority view, the survey also indicates a noteworthy, if limited, level of growing support.

5. Japan–U.S.–South Korea Security Cooperation

• Regarding strengthening security cooperation among Japan, the U.S., and South Korea, 51.7% were “in favor,” while 27.7% were “opposed.” Reasons for support included “curbing China’s military rise” (56.5%) and “responding to North Korea’s nuclear and missile threats” (53.2%), indicating strong backing for maintaining the U.S.-led security framework. Reasons for opposition included “escalating tensions” (43.9%), “deteriorating relations with China” (31.7%), and “distrust due to historical issues” (29.3%).
• Regarding the presence of U.S. forces in Japan, 49.5% said they “contribute to peacekeeping,” while 33.5% answered they “do not contribute,” reflecting divided public opinion. On the issue of stationing costs, 56.7% answered “too much,” far exceeding the 19.8% who said “appropriate” and the 3.7% who said “should bear more.”
• As for Japan’s defense expenditures, 7.3% responded “should be increased significantly” and 26.4% “should be increased to some extent,” with a combined 33.7% supporting an increase. “Maintain current levels” was close at 32.9%, while “should be reduced” reached 16.9%. These results suggest that while the public recognizes the need to strengthen deterrence, opinions are divided on increasing defense spending, and a strong cautious stance toward the fiscal burden remains evident.

6. Economic Relations and Foreign Worker Acceptance

• Countries and regions deemed economically important to Japan were the United States (66.4%), China (37.3%), the EU (37.1%), ASEAN (37.0%), and India (35.9%). Regarding the China-related restrictions the U.S. is demanding of Japan and South Korea, 26.5% were in favor and 50.3% opposed, reflecting a cautious public stance.
• Regarding the increase in foreign tourists visiting Japan, 29.4% were in favor, while 50.7% were opposed, meaning opposition accounted for the majority. Reasons for support included “revitalizing the local economy through tourism spending” (74.3%) and “expanding diversity through promoting cross-cultural exchange” (34.9%), reflecting expectations for economic benefits and cultural stimulation. Conversely, reasons for opposition included “deterioration of living environments due to crowding, noise, litter, etc.” (75.7%), “friction between tourists and local culture” (72.4%), and “concerns about public safety” (58.2%), highlighting strong awareness of the social costs associated with the government’s tourism-oriented policy.
• Meanwhile, regarding the increase in foreigners residing in Japan, 20.6% were in favor and 57.8% were opposed, revealing an even more cautious stance. Reasons for support included “securing labor to address shortages” (68.2%), “promoting diversity in Japanese society” (45.3%), and “halting population decline in rural areas” (32.7%), reflecting pragmatic expectations regarding the labor market and demographic trends. The main reasons for opposition were “concerns about worsening public safety” (74.5%), “friction with culture and customs” (73.5%), and “strain on social infrastructure such as healthcare, education, and welfare” (45.4%), underscoring anxieties about social integration and the burden on public services.
• These results reveal a tension within Japanese society between the economic and demographic need to accept foreigners and concerns over public safety, cultural differences, and infrastructure burdens. While many anticipate positive benefits such as tourism and labor force expansion, these expectations are counterbalanced by worries about the costs of social integration. This suggests that designing effective acceptance systems and building social consensus will become key political priorities moving forward.

Summary
This survey reveals that public opinion within Japan reflects complex views on Japan–U.S.–South Korea relations, security, and social policy.

First, recognition of the Japan–U.S. alliance as indispensable is widely shared. At the same time, strong anxieties about dependence on the United States are evident, driven by distrust of the U.S. president, concerns over stationing costs, and the burden of defense expenditures. With regard to South Korea, cultural exchanges are seen in a positive light. Yet deep-rooted distrust continues due to historical and territorial issues, revealing a persistent duality in public sentiment.

On the possibility of a Taiwan contingency, many respondents believe it is likely to occur and view it as extremely important for Japan’s national interests. However, opinions are divided over Japan’s role, with some favoring limited logistical support and others preferring to avoid military involvement altogether. Both Japanese and South Korean nuclear armament were strongly rejected, underscoring the difficulty of reconciling reliance on the U.S. nuclear umbrella with the public’s desire for reassurance.

Furthermore, opinions on increasing defense expenditures are closely divided. Many acknowledge the need to strengthen deterrence, yet strong concerns remain about the fiscal burden. On the issue of accepting foreign tourists and residents, expectations of economic benefits and relief for labor shortages clash with anxieties over public safety and pressure on social infrastructure. This underscores the importance of careful system design and building social consensus.

Overall, these findings indicate that Japan’s security and foreign policy face a significant challenge going forward: not only strengthening deterrence, but also fostering public understanding and building social consensus.

Authors: Ken Jimbo, Misato Nagakawa, Masashi Yui