K-Buzz

The US-South Korea alliance has returned to the center of public debate.
The documentary "Legacy of the Battlefield" will be screened in Washington, DC.
The screening is an opportunity to reexamine the alliance's past and present.
Public opinion and policy divisions are fueling further discussion of the film.

US-Korea alliance: Past shadows over today

Overview

We face facts.

The US-South Korea alliance is a security partnership centered on American forces stationed in South Korea and on joint military exercises to deter threats from North Korea.

In February 2026, the documentary "Legacy of the Battlefield" is screened in Washington, DC.
The film revisits what the alliance has meant and how it has changed, and it raises questions about mutual perceptions and policy shifts between the two countries.
This column uses the screening as a starting point to reconstruct the alliance's structure and the central debates.
Meanwhile, it compares public-opinion surveys and recent policy disputes to paint a three-dimensional picture of the pro-and-con camps.

Historical context

We recall history.

Since the 1950s the alliance has been a core pillar of security on the Korean Peninsula and has adapted through Cold War and post-Cold War shifts.

The US-South Korea partnership formed in the shadow of the 1950–53 Korean War, and its meaning evolved through Cold War rivalry and later strategic competition with China's rise.
During the authoritarian decades under Park Chung-hee and Chun Doo-hwan, human rights and democratization caused friction, yet strategic alignment sustained the alliance.
Under President Jimmy Carter the US considered withdrawing forces from Korea, but Congress blocked full withdrawal.
Recently, debates have resurfaced as US-China competition intersects with North Korea’s advancing nuclear and missile programs, prompting new questions about the alliance's role and scope.

Arguments for strengthening

Advocates press for reinforcement.

Supporters argue that modernizing the alliance offers the best response to China's military expansion and to North Korea's growing capabilities.

First, supporters emphasize security realities.
China's military buildup and North Korea's improved nuclear and missile capabilities have broadened the peninsula's threat environment.
Therefore, the presence of US forces in Korea and regular joint exercises enjoy strong backing both in South Korea and among many Americans.
For example, polls find about 87% of South Koreans say US forces in Korea are necessary, and roughly 88.8% support joint exercises—numbers that supporters cite as clear evidence of popular consensus.

Second, they argue for stronger deterrence.
The alliance should evolve beyond a simple troop presence toward enhanced extended deterrence (the US pledge to use force, including nuclear options, to protect an ally), intelligence sharing, and improved combined operational capabilities.
Proponents point to missile defenses such as THAAD deployment and trilateral cooperation with Japan as means to build layered responses to regional threats.
Moreover, surveys show that when confidence in the US nuclear umbrella is high, popular support for expanding the alliance's role tends to increase.

Third, they highlight political and economic interests.
Security cooperation often yields diplomatic stability, attracts investment, and deepens technological and defense industrial ties.
Supporters argue that modernizing the alliance strengthens the South Korean military while improving the efficiency of combined defense posture.

Finally, they frame the nuclear debate pragmatically.
Some public sentiment for an independent Korean nuclear capability rose during periods of alliance uncertainty, notably during the Trump administration.
Proponents say that instead of pursuing unilateral nuclearization, Seoul should solidify security through extended deterrence and discussions on nuclear sharing within the alliance framework.

Arguments for restraint

Opponents favor limits.

Critics say the alliance should focus on deterring North Korea and be careful about widening its role to counter China.

Opponents first contest the alliance's scope.
They warn that if the US presence in Korea becomes a forward base against China, Seoul will inherit strategic burdens it did not ask for.
About 40.1% of South Koreans say the alliance's role should be limited to North Korea, a statistic that reflects these concerns.
They argue that expanding the alliance's posture risks stoking regional tensions and exposing Korea to greater geopolitical risk.

Second, critics raise sovereignty and autonomy issues.
Excessive dependence on the alliance can undermine South Korea's strategic independence.
Some policies—like reducing joint exercises or pursuing a diplomatic approach to Pyongyang—have provoked tensions with Washington, but defenders of these measures frame them as efforts to reclaim policy space rather than reject the alliance.
They prefer diplomacy and economic tools over military-first responses.

Third, they warn about the dangers of nuclearization.
An independent Korean nuclear arsenal could trigger an arms race with neighbors and isolate Seoul internationally.
While some regions in Korea showed higher support for nuclear options, opponents caution that unilateral moves would likely increase insecurity rather than reduce it and could deepen fractures within the alliance.

Finally, they point to costs and social division.
Issues such as burden-sharing for US forces, public opposition to closer military ties with Japan, and domestic political polarization are practical concerns opponents raise.
They call for transparent cost-sharing arrangements and stronger democratic oversight while keeping the alliance's role measured.

Causes and structure

We look for root causes.

Debate over the alliance sits where shifts in the international order meet domestic politics.

The dispute is not just ideological.
It stems from three structural shifts. First, China's growing military strength and influence have altered the regional security landscape.
Second, North Korea's nuclear and missile advances have called into question traditional deterrence approaches.
Third, uncertainty in US domestic politics and foreign policy has prompted allies to reconsider contingency plans.

These structural changes feed public opinion.
In South Korea, rising security anxieties have increased support for US forces and joint exercises while also energizing calls for greater autonomy.
In the United States, attitudes toward forward deployments vary by age and political outlook, according to research.
Ultimately, the alliance is shaped by a complex interaction of foreign policy variables and domestic political dynamics.

Interaction of public opinion and policy

Policy responds.

Public opinion influences policy, and policy choices in turn reshape public views.

High public support for maintaining US forces and for joint exercises lends political legitimacy to those policies.
However, leaders' decisions and shifts in international conditions can move opinion quickly.
For example, uncertainty in the alliance during the Trump administration coincided with a rise in public support in South Korea for independent nuclear options.
Thus foreign policy shifts can combine with domestic opinion to create new political demands.

Conversely, reductions in exercises or diplomatic outreach to the North can strain the alliance.
Some actions by the Moon Jae-in administration were judged by critics to have stressed US-ROK relations, and the ensuing political debate raised questions about alliance stability.
Policy makers therefore need the capacity to balance international constraints with domestic sentiment.

A framework for realistic choices

Decision points appear.

Seoul must design the alliance's scope by weighing security, diplomatic, and economic factors together.

In practice South Korea faces several options.
First, strengthen the alliance to increase deterrence. This would mean expanding joint exercises, deepening intelligence and military integration, and intensifying trilateral cooperation with Japan.
Second, limit the alliance's role and pursue diplomatic solutions, which would reduce military tensions and emphasize independent diplomatic capacity.
Third, pursue a middle path of strategic autonomy: maintain the alliance while seeking greater policy control and room for maneuver.

Each choice carries benefits and costs.
Strengthening the alliance offers immediate deterrence but may raise geopolitical tensions.
Limiting the alliance can ease domestic unease but leave gaps against external threats.
The middle path demands intricate diplomacy and consistent policies to succeed.

Conclusion and questions

We summarize the key points.

Debate over the alliance goes beyond simple pro-or-con answers; it requires strategic choices and broad social agreement.

The US-South Korea alliance has long been central to South Korea's security, and it is likely to remain important.
However, disputes about the alliance's role and limits will continue. Policy decisions must balance realistic threat assessments with democratic consensus.
Both proponents and opponents offer persuasive arguments, and each position broadens the range of diplomatic and security options available to Seoul.

Nuclearization, joint exercises, and the presence of US forces in Korea are not simple issues.
They are complex decisions at the intersection of global order, domestic politics, and public sentiment.
In conclusion, the alliance's future should be pursued through diplomatic prudence and national consensus.
Which option do you think would best promote South Korea's long-term security and prosperity?