Any cross-Strait military conflict would have clear implications for other countries in the region, yet little attention has focused on public opinion regarding the issue outside of Taiwan. Our survey work on South Korean perceptions highlights the potential challenges in coordinating a regional response to such a contingency: finding broad acknowledgment of the potential ramifications, yet a hesitancy to take actions that would likely worsen relations with China.
Cross-Strait tensions have increased since the election of Taiwan’s President Tsai Ing-wen (蔡英文) in 2016. Such antipathy could escalate further if presidential frontrunner Lai Ching-te (賴清德) is victorious in Taiwan’s 2024 national elections, as China aims to coerce Taiwan’s government into actions consistent with its demands for eventual unification. Frequent Chinese military drills after Nancy Pelosi and other US officials visited Taiwan in 2022 suggest the possibility of the further intensification of such exercises in the future. Many have likened Taiwan’s situation to that of Ukraine—a comparison that survey evidence suggests has been made by Taiwanese citizens as well. Specifically, the conflict has influenced perceptions about Taiwan’s ability to defend itself, though many Taiwanese remain divided as to whether the United States will defend them. In general, any cross-Strait military conflict would have serious ramifications globally, as it would adversely affect international trade—particularly the worldwide distribution of semiconductors, of which Taiwan is a leading exporter.
Despite the widespread concern over potential conflict, remarkably little attention has been given to public opinion in other regional democracies. In a hypothetical Chinese invasion scenario, US military assistance to Taiwan likely would depend on Japan allowing US forces to conduct military operations from Japanese soil. Furthermore, many expect that South Korea would also play a role in Taiwan’s defense, given its previous assistance to US campaigns in Vietnam and Iraq. An August 2022 survey found a majority (64.5 percent) of South Koreans supported providing direct or indirect support for US efforts to defend Taiwan. However, this does not give any indication what this support would entail, or if the public fully grasps the political and economic costs of such an action, which could potentially result in direct Chinese retaliation against South Korea. Such a conflict, even without South Korea’s direct involvement, would likely halt much of the international trade in Northeast Asia and damage crucial submarine cables. Such disruptions could cost Japan and China 3.7 percent and 7.6 percent, respectively, of their nominal GDP.
Understanding South Korean Perceptions of Taiwan
South Korea shares many historical and political similarities with Taiwan, with both experiencing Japanese colonization, post-war rapid economic development and democratization, and security relationships with the United States. These factors could contribute to South Korean affinity for Taiwan, conceivably resulting in increased Korean support for the island democracy. However, such assistance could also lead to Chinese retaliation, potentially including encouraging North Korea to instigate conflict to thwart such efforts.
To understand Korean perceptions of Taiwan and cross-Strait relations, we conducted a national web survey of 1,300 South Koreans (conducted from September 27-October 11, 2023) via quota sampling on gender, age, and region, administered via the survey company Macromill Embrain. We randomly assigned respondents to one of two questions about cross-Strait conflict as a means to identify whether the public may be more supportive of economic versus military intervention:
Version 1: If China were to start a conflict with Taiwan, would you support South Korea enacting economic sanctions against China?
Version 2: If China were to start a conflict with Taiwan, would you support South Korea providing military assistance to Taiwan?
The results suggest a public hesitant to respond against China, with more willingness to engage in economic sanctions (45.21 percent) than to provide military assistance to Taiwan (34.39 percent), despite South Korea’s clear abilities to manufacture relevant equipment in a timely manner. This likely points to perceived risks with each option, with the latter more likely to be viewed as an escalation by China. Broken down by political party support, we see a stark difference: with supporters of the center-left Democratic Party (DP) showing little support for either option (V1: 34.27 percent; V2: 27.03 percent), while a majority of supporters of the center-right People Power Party (PPP) supported both options (V1: 62.89 percent; V2: 54.35 percent).
Graphic: South Korean public support for involvement in a Taiwan Strait contingency in response to queries about economic sanctions and military assistance, broken down by party affiliation. (Source: research by authors.)
Predictably, views of China and Taiwan also influence willingness to act. We asked respondents to rate both countries on a 1-10 scale, with 10 being most favorable. We find those scoring China at 5 or below were more supportive of both measures (V1: 46.26 percent, V2: 34.69 percent), as compared to those scoring 6 and above (V1: 35.48 percent; 31.94 percent). Conversely, more positive evaluations of Taiwan corresponded with greater willingness to act. Using the same metrics, those scoring Taiwan at 5 or lower were less supportive of action (V1: 38.87 percent, V2: 30.54 percent) compared to those with more positive views of Taiwan (V1: 52.53 percent; V2: 39.25 percent). Of note, views of the two countries seem to have a far bigger impact on support for sanctions.
After this, we asked several related questions. First, when asked “If China were to attack Taiwan, do you believe that it would have very serious implications for South Korea?,” 89.15 percent of respondents said yes, with little difference between DP supporters (88.15 percent) and PPP supporters (91.92 percent). Similarly, when asked “If the US did not defend Taiwan, do you believe that it would have very serious implications for South Korea?,” 85.85 percent said yes, with slightly more variation by party (DP: 83.75 percent; PPP: 89.56 percent). Finally, when asked “If the US did not defend Taiwan in the case of an attack by China, how worried would you be that the US would also not support South Korea if North Korea were to attack?” Here, a slight majority (50.16 percent) stated that they were moderately to extremely worried, although this varies notably by partisan identification (DP: 45.18 percent; PPP: 62.29 percent).
Graphic: South Korean public perceptions of US support for Taiwan and South Korea. (Source: research by authors.)
Taken as a whole, our results suggest a South Korean public clearly aware of the potential ramifications of a cross-Strait conflict, yet hesitant to commit to efforts to respond to China in the case of an invasion of Taiwan, suggesting broader fears about the consequences of an invasion for South Korea. With China as South Korea’s top trading partner, the thought of imposing economic sanctions may create fears of counter-sanctions. Likewise, providing military assistance to Taiwan would not only likely worsen relations with China, but could also potentially incentivize China to use its influence with North Korea to heighten security concerns on the peninsula.
Admittedly, responding to hypothetical situations—even ones that receive considerable media attention—cannot fully capture how South Koreans may feel in the event of an actual invasion. However, the results suggest that if such an invasion were to occur in the short term, President Yoon Suk Yeol—already facing very low public approval ratings within a deeply polarized South Korea—would likely struggle to garner broad support for retaliatory actions.
Whereas previous studies have demonstrated high support among Koreans for the US military to provide aid to Taiwan, our survey did not explicitly mention US support (other than in the context of continued support for bases in South Korea). Taken together, this result demonstrates that South Koreans may be supportive of US efforts to defend Taiwan and simultaneously concerned that a US failure to do so could portend diminishing US support for South Korea. However, they remain cautious about how their actions to aid Taiwan could risk their own economic and security interests. Accordingly, the challenge for both US and South Korean administrations will be in coordinating potential responses that secure their own interests while also effectively limiting Chinese aggression.
The main point: While South Koreans are undoubtedly aware of the potential ramifications of a Chinese attack on Taiwan for South Korea, survey data suggests that many are reluctant to support direct Korean involvement in such a conflict. These results could pose challenges to the United States, South Korea, and Taiwan.