Asan Issue Brief Release:
“Worth the Squeeze: A Conditions-based Analysis of South Korean Public Support for Nuclear Deterrence”

 
SEOUL, May 28, 2025 – Dr. Peter K. LEE and Mr. KANG Chungku of the Asan Institute’s Center for Regional Studies (http://en.asaninst.org/) have published a new Asan Issue Brief, titled “Worth the Squeeze: A Conditions-based Analysis of South Korean Public Support for Nuclear Deterrence.”

The Issue Brief introduces the results of a series of conditions-based questions to test the robustness of South Korean public commitment to enhanced nuclear options.

• The five conditions include a willingness to face international sanctions, risk the withdrawal of U.S. forces from the Korean Peninsula, build storage facilities and conduct nuclear tests, increase defense cost-sharing with the United States, and host tactical nuclear weapons in their city or province.

•The Issue Brief finds that a majority of the South Korean public is now committed to both nuclear armament and nuclear redeployment even in the face of four out of five potential cost conditions due to record-high threat perceptions and concerns about the U.S. security commitment.

•The high headline support for nuclear armament (76.2%) and nuclear redeployment (66.3%) means that even substantial drops in support no longer fall below majority support.

•“The results suggest that, for a majority of the South Korean public, the nuclear juice is worth the squeeze of potential costs,” the researchers argue.

However, the South Korean public is most sensitive to specific and tangible potential costs that have a direct impact on them, including hosting deployment of weapons as well as storage and testing facilities in their locality, whereas abstract and unspecified costs only have a modest impact on commitment.

•While indigenous nuclear armament appears to enjoy higher levels of support over nuclear redeployment, rather than being indicative of public preference, the authors hypothesize that more specific and tangible cost conditions would quickly erode the headline figure given indigenous nuclear armament will involve much higher costs, potentially involving all five conditions occurring simultaneously, than nuclear redeployment within an alliance framework.

The Issue Brief proceeds as follows:

1. First, it explains the failure of existing ROK-U.S. extended nuclear deterrence measures to reassure the South Korean public, whose threat outlook is more severe than ever. It shows that alternative nuclear options have record levels of support, including indigenous nuclear armament and the redeployment of U.S. nuclear weapons.

2.Second, it reviews the three conditions used to test the strength of public commitment to indigenous nuclear armament, including a willingness to face international sanctions, risk the withdrawal of U.S. forces, and build storage facilities and conduct nuclear tests.

3.Third, it reviews the two conditions for nuclear redeployment, including a willingness to increase defense cost-sharing with the United States and host tactical nuclear weapons in their city or province.

4.Fourth, it discusses policy implications and offers recommendations, including about the strength of headline support, the role of specific and tangible costs, the viability of nuclear redeployment over indigenous armament, and the need for further survey experiments and focus group interviews to identify the specific pathways for maintaining support for stronger nuclear options.

•“The findings suggest that existing assumptions need to be revisited in the strategic context of 2025—characterized by heightened North Korean threats and eroding trust in U.S. extended deterrence,” the authors contend.

Inquiries:

Dr. Peter K. Lee, Research Fellow (peter.lee@asaninst.org)
Mr. KANG Chungku, Principal Associate (Public Opinion Studies Team Lead) (ckkang@asaninst.org)

The Asan Institute for Policy Studies is an independent, non-partisan think tank dedicated to undertaking policy-relevant research to foster domestic, regional, and international environments conducive to peace and stability on the Korean Peninsula.