Korea’s strategic reality: Trust America, prepare for the future

Chun In-bum

The latest public opinion poll from the Asan Institute for Policy Studies, a Seoul-based think tank, shows that South Korea is becoming more realistic but not less anxious. The old assumptions that shaped South Korean foreign policy for decades are changing. Public views of Japan are improving. Trust in the United States remains strong, despite skepticism toward President Donald Trump. At the same time, South Koreans believe the country must prepare itself for a world that is more dangerous, less stable and less predictable.

The clearest shift is seen in the South Korean public's attitude toward Japan. Japan’s favorability rating rose to 5.11 out of 10, the first time it has moved above the midpoint and the highest level ever recorded in the survey. Japanese Prime Minister Sanae Takaichi was also the most favorably viewed foreign leader, ranking above Trump. That would have been hard to imagine a decade ago. It suggests that many South Koreans are increasingly willing to treat Japan not only as a historical problem, but as a present-day strategic partner.

This does not mean historical grievances have disappeared — they have not. But it does suggest that more South Koreans are separating unresolved history from current security needs. Seoul and Tokyo face common pressures from North Korea’s advancing nuclear program, China’s growing assertiveness, Russia’s closer alignment with both Pyongyang and Beijing, supply chain vulnerabilities and broader instability in the Indo-Pacific region. President Lee Jae Myung’s diplomacy with Japanese leaders appears to have helped stabilize the relationship. Geography is doing what history long prevented and forcing realism.

At the same time, the poll found the United States is still regarded as South Korea’s most important ally by a wide margin. In the Asan survey, the United States received the highest country favorability score at 5.90. About 74.7 percent of respondents identified the United States as South Korea’s most important economic partner, and 64 percent still chose it as South Korea’s most important security partner. Support for the South Korea-U.S. alliance reached a record 97.1 percent, and support for the continued U.S. military presence in Korea reached 82.3 percent, also the highest level recorded in the survey.

That matters because it shows that South Koreans continue to distinguish between Trump and the United States as a country. Trump’s personal favorability rating fell to 2.91, yet confidence in the United States remained strong. Even more striking, public optimism about the future of South Korea-U.S. relations improved sharply. In 2025, many South Koreans feared relations would worsen as Trump returned to office. In 2026, 55.3 percent said they believed relations with the United States would improve. In plain English, many Koreans may not like Trump but they still trust America more than the alternatives.

That is a rational judgment. No other country can provide South Korea with the same combination of extended deterrence, intelligence support, advanced military technology, missile defense, naval power and diplomatic influence. China cannot. Japan cannot. Europe cannot. South Koreans appear to understand that. Even in a period of alliance friction, they still see the United States as the indispensable external pillar of Korean security.

But the survey also shows something else, and this is where the real strategic shift begins: South Koreans are no longer content to rely only on the alliance. They increasingly believe the country must be better prepared to defend itself.

The strongest evidence appears in attitudes toward nuclear deterrence. Public confidence that the United States would use nuclear weapons to defend South Korea rose to 59.1 percent. Nearly half also believed Washington would still do so even if that meant accepting possible danger to the U.S. homeland. That is a meaningful rise in confidence and suggests that faith in U.S. extended deterrence remains real.

Yet greater confidence in the American umbrella has not reduced support for South Korea acquiring its own nuclear weapons — quite the opposite. Support for a nuclear arsenal reached a record 80 percent. Even when respondents were told that pursuing nuclear weapons could invite international sanctions, impose costly domestic infrastructure burdens or even risk the withdrawal of U.S. forces, support still remained above 50 percent in every case. That is not a fringe impulse — it is mainstream thinking. Many South Koreans increasingly see nuclear armament not as a radical option, but as insurance.

Why? Because the security environment surrounding South Korea has worsened. North Korea continues to expand its nuclear and missile arsenal. Military cooperation between Pyongyang and Moscow has deepened. Inter-Korean dialogue remains frozen. China is more assertive at sea and more coercive across the region. Russia is now more openly aligned with both China and North Korea. In that environment, many South Koreans appear to be concluding that while the alliance remains essential, it may not always be sufficient on its own. That is not panic but strategic adaptation.

The survey also shows a more sober view of the future balance of power between the United States and China. When asked which country would be stronger in ten years, 46 percent still chose the United States, compared with 15.1 percent for China. But that confidence has declined, and more respondents now expect a long period of rivalry in which neither side dominates completely. South Koreans appear to believe the future will be contested, not comfortably American-led.

Even so, when asked which country South Korea should side with if U.S.-China competition continues, 71.4 percent chose the United States, while only 10.8 percent chose China. That may be the most important figure in the entire survey. South Koreans may think the international system is becoming multipolar, but when forced to choose, they still overwhelmingly trust the United States over China.

For policymakers, the implications are straightforward.

First, South Korea should continue strengthening the alliance with the United States. That means deeper combined deterrence, tighter intelligence cooperation, stronger missile defense, more resilient supply chains and closer coordination in cyber and advanced technologies. The alliance remains the foundation of the country's security and prosperity.

Second, South Korea should continue improving relations with Japan. The logic is simple: Seoul and Tokyo do not have the luxury of remaining trapped in the past while North Korea, China, and Russia cooperate in the present. History still matters, but geography is stubborn and does not negotiate.

Third, South Korea must invest more seriously in its own defense capabilities. That does not automatically mean building nuclear weapons tomorrow. The costs and risks would be real. But it does mean preparing for a future in which Korea needs stronger missile defense, larger stockpiles, stronger civil defense, better cyber resilience, more capable naval and air power and a more self-reliant defense industrial base. Hope is not a defense plan.

The Asan survey does not describe a South Korea that is abandoning the United States. It is a South Korea that still trusts America, but no longer assumes America will be enough. That is not anti-Americanism. It is strategic maturity. In a harsher world, South Koreans believe in staying close to the United States, working more closely with Japan and preparing to stand on their own feet.

Retired Lt. Gen. Chun In-bum is the former commander of the Republic of Korea Army Special Warfare Command.