A Security–Economics Trade-off? Public Support for the Quad in South Korea

Abstract With a security alliance with the United States and deep economic relations with China, South Korea faces complex foreign policy choices amid US–China competition. A critical decision is whether to join the Quadrilateral Security Dialogue (Quad), a US-led grouping widely viewed as aiming to counter China in the Indo-Pacific. The choice depends on its domestic politics as much as its relationships with both superpowers. Using a public opinion survey with a priming experiment, we investigate South Korean citizens’ preferences regarding the Quad. We find that, without additional information, nearly half of the respondents supported joining the Quad. Yet neither mentioning the security benefits of joining the Quad nor mentioning the potential economic costs associated with Chinese retaliation for joining the Quad changed their level of support. Nor did we detect any treatment heterogeneity. Beyond the experiment, we find that threat perceptions and party affiliation are strongly correlated with respondents’ preferences.