Issue Briefs



The deployment of THAAD (Terminal High Altitude Area Defense) on the Korean Peninsula is rapidly changing Korea’s relationships with its two most important partners, the United States and China. The initial estimation, as offered by U.S. Forces Korea (USFK) Commander Gen. Vincent K. Brooks, was that the American missile defense system would be deployed sometime in the summer of 2017. As of March, however, parts of the THAAD battery have already landed in Korea. While more time is needed to prepare the site in Seongju, it appears likely that a fully operational THAAD system could be installed much earlier than initially anticipated. China has responded aggressively, banning imports of Korean cultural products and cracking down on tourism to Korea. Lotte Group, the Korean conglomerate that agreed to a land-swap deal with the Korean government that would allow THAAD to be placed in Seongju, has been the target of retaliation by the Chinese government, as well as Chinese consumers who have boycotted Lotte products.

These developments are likely the result of calculated assessments by the American and Chinese governments to capitalize on now-former President Park Geun-hye’s impeachment proceeding and the resulting leadership vacancy in Korea. The United States has calculated that an early deployment of THAAD would be the best course of action, as President Park’s impeachment will likely place a progressive government in the Blue House. On the other hand, China has focused its anger at Lotte Group, although it has refrained from targeting more Korean companies for the time being. China is likely awaiting the result of the presidential election and hoping that the next administration will work together to address the issue in its favor.

The past three months have been a very interesting time for Koreans. They not only went through one of the worst political crises in their history, but also witnessed the election of U.S. President Donald Trump and saw the Korean Peninsula become a battleground for U.S.-China rivalry over THAAD. As a result, their opinions toward the missile defense system and their two most important partners have shifted. This issue brief examines the Asan Institute’s recent public opinion survey results to identify how and why their opinions have undergone changes.

This issue brief makes the following conclusion: Since January of this year, favorability of China among Koreans dropped precipitously to a level even below to that of Japan’s. This deteriorating perception was a result of Chinese retaliation for the deployment of THAAD on the Korean Peninsula. Favorability of the United States also dipped slightly. Compared to November 2016, more Koreans now support and fewer oppose the deployment of THAAD. This shift in favor of the American missile defense system was made possible by older Koreans over the age of 60 who have strong attachment to former President Park and possess anti-China sentiments. Overall, Koreans have responded negatively toward what they consider to be excessive interference by regional superpowers on Korean issues.

Country Favorability

One of the surprising results from our March 2017 public opinion survey was the sharp decline in China’s favorability among Koreans. Although a drop was expected and perhaps inevitable given Chinese response to THAAD, China’s rating fell by more than a full point. On a scale of 0 to 10 (0=least favorable, 10=most favorable), China’s rating in January 2017 was 4.31, which dropped to 3.21 in early March. This draws stark contrast to the survey result from September 2015, when former President Park attended the military parade in Tiananmen Square and showed great rapport with Chinese officials, including President Xi Jinping.2 Korea was the only American ally to attend the parade.

Even more surprising is that Koreans are now more favorable toward Japan (3.33) than China (3.21). Until now, Japan has consistently been Koreans’ least favored country, with the exception of North Korea. The December comfort women agreement and the controversy over the comfort women statue still continue pose an obstacle toward improved ROK-Japan relations. Yet, Japan’s favorability rating declined only slightly, while China’s suffered a precipitous drop. This shows just how much Koreans’ perception of China has changed as a result of China’s economic retaliation for THAAD.

Historically, Koreans have shown strong resentment when great powers have fought over the Korean Peninsula or have interfered with Korea’s domestic issues. Consequently, Koreans’ favorability toward the United States also dropped slightly from 5.77 in January to 5.71 in March. However, it is difficult to attach much meaning since China suffered a greater hit.

Figure 1. Country Favorability Rating3
(0=least favorable, 10=most favorable)


Declining favorability toward China was most noticeable among elderly Koreans. In the past, when ROK-China relations were at their peak, Koreans aged 50 and older viewed China most favorably.4 This was due to their support for President Park, which then translated to their approval of her pro-China policies. In other words, they were simply supporting the policies of their leader, rather displaying a fundamental change in the way they saw China. This explains why elderly Koreans were so quick to turn against China in recent months. Moreover, elderly Koreans are generally ultra conservative toward security issues, which worked against China when it interfered in Korea’s security decision. China’s favorability also suffered significant drops among younger Koreans in their 20s and 30s although not as much as older Koreans.

Figure 2. Favorability Rating of China, by Age5
(0=least favorable, 10=most favorable)


We examined Koreans’ favorability of the United States from January-March 2017 and noticed an interesting trend. Unlike China’s numbers, which declined in all age groups, favorability of the U.S. diverged across different age groups. The overall number remained more or less similar to the past (mid to high 5), but this was made possible by an increasing number of conservative Koreans over the age of 60 who have come to favor the United States more.

For instance, the favorability score of the U.S. in January ranged from 5 and 6 across age groups with minor discrepancies. In March, however, favorability of the U.S. among Koreans aged 60 and older almost reached a score of 7.6 In other age groups, the numbers either remained steady or declined. The decline was most visible among Koreans in their 40s whose favorability dropped from 5.32 in January to 4.76 in March. This cancelled out the high number from Koreans aged 60 and older, whose rating rose from 6.56 in January to 6.96 in March. For the United States, the most worrisome number belonged to Koreans in their 20s. In the past, they, along with older Koreans, were most supportive of the United States. They were strongly pro-American due to their conservative mindset on security issues and their admiration of American soft power. The fact that their favorability has declined consistently, albeit gradually, is an important development worth noticing.

Figure 3. Favorability Rating of the U.S., by Age7
(0=least favorable, 10=most favorable)


Leadership Favorability

We examined the favorability of President Trump and President Xi Jinping among Koreans. Not surprisingly, favorability of President Xi shifted the most. His rating was 4.25 in January 2017 which dropped by 1.24 points to 3.01 in March. This was the largest drop for President Xi since July 2013. Also, this draws stark contrast to 2014 when ROK-China relations reached a pinnacle and President Xi’s favorability rating, well over 5, was closely chasing President Barack Obama’s.8 The only good news for President Xi was that his rating remained higher than Prime Minister Abe’s.

U.S. President Donald Trump’s rating also stumbled. His rating had hovered around 1 during the election campaign, which rose to around 3 after being elected as president. He failed to maintain the momentum, however, as his rating dropped by 0.56 point from 3.49 in early January to 2.93 in March. Endless speculations and criticisms about his presidency, including his immigration and trade policies, appear to have contributed to his declining favorability among Koreans.

Figure 4. Leadership Favorability9
(0=least favorable, 10=most favorable)


Interestingly, while numbers for China, President Xi, and President Trump all fell all fell, the United States’ favorability remained steady. Unlike President Obama, whose favorability rating contributed greatly to the high rating of the United States, President Trump does not appear to possess a similar attraction for Koreans. At the same time, it appears that President Trump’s low favorability has not influenced how Koreans see the United States, which proves just how much Koreans value the United States as a military ally and consider the U.S. in a positive light. It also confirms the role that older Koreans have played in supporting the United States. Since the U.S. election in November, favorability of the U.S. among Koreans in their 20s, 30s, and 40s have all shown minor decline while Koreans aged 60 or more have maintained their favorability.

The rapid decline of China’s favorability shows that Korea’s relationship with China is fundamentally different from its relationship with the United States. Korea and the U.S. have maintained a close relationship based on a military alliance that has withstood the test of time. On the other hand, Chinese reaction to THAAD has not only lowered Koreans’ favorability of China to a level below to that of Japan but also dragged down President Xi’s number as well. The fact that China’s rating dropped so suddenly and so quickly proves that the favorable ROK-China relations of the past few years failed to evolve into a strong and stable cooperative relationship. Unlike with the U.S., the usual supporters of China—Koreans aged 50 and older—turned their backs when China reacted negatively to THAAD.

ROK-U.S. and ROK-China Relations

We asked Koreans how they felt about Korea’s relationships with China and the United States. In particular, we asked them if they consider Korea’s relationship with the two countries to be competitive or cooperative in nature. 52.7% of respondents thought ROK-China relations were competitive while 38% thought relations were cooperative. This result was a complete reversal from last year’s. In response to the same question in March 2016, 38% of Koreans saw ROK-China relations as competitive while 56.9% saw them as cooperative. Perception of the relationship between two countries began to aggravate in August 2016, just as THAAD was becoming an issue.10 When we examined the results by age, a decreasing number of Koreans in all age groups saw the relationship as cooperative. The biggest change came from Koreans in their 20s whose number fell by 25.2% (from 56.8% in March 2016 to 31.6% a year later). They were closely followed by Koreans aged 60 and older (23.5%, 52.6% à 29.1%) and Koreans in their 50s (20.6%, 59.3% à 38.7%).

Perception regarding the nature of the ROK-U.S. relationship also went through change. While the majority still saw the two countries’ relationship as cooperative, the number fell slightly when compared to last year’s. In March 2016, 86.1% of Koreans identified ROK-U.S. relations as cooperative. In March 2017, this number dropped slightly to 79.5%. While the most recent number is still sky high, the drop was likely the result of the THAAD controversy in addition to fallouts from President Trump’s “America First” politics.

Figure 5. Nature ROK-U.S. and ROK-China Relations (%)11



What do Koreans think about the deployment of THAAD and how have opinions changed over the course of two years? The Asan Institute has been tracking Korean public opinion on THAAD since March 2015. Our most recent survey results show that Koreans’ opinion about THAAD has indeed changed. Support for THAAD was highest in the immediate aftermath of North Korea’s fourth nuclear test in February 2016, when 73.9% supported the American missile defense system. However, the numbers continued to decline as THAAD became politicized in Korea. In November 2016, 46.3% approved while 45.7% disapproved of THAAD (within the margin of error).12 When asked about the reason for their disapproval, 53.9% of Koreans answered that they did not trust the government’s decision. This was also the time when public demand for President Park’s impeachment was at its peak. Between March 6-8 of this year, as the impeachment proceeding was coming to a conclusion, support for THAAD rose to 50.6% (37.9% disapproved). This was likely related to elderly Koreans’ attitudes toward former President Park and their displeasure at China for its retaliation over THAAD.

Figure 6. Public Opinion on THAAD (%)13


THAAD and Domestic Politics

Our survey results show that shifting opinion toward THAAD has much to do with Korea’s domestic politics. What was noticeable about this shift was the difference in opinion according to age. In our most recent survey, 32.9% of Koreans in their 30s and 40.3% in their 40s approved while 59.5% and 48.2%, respectively, disapproved of THAAD. On the other hand, 56% of Koreans in their 50s approved (32.5% disapproved) and 73% of Koreans aged 60 and older approved (13.9% disapproved).14

Another interesting development was the direction in which opinions diverged according to age. In 2015 and 2016, opinion on THAAD moved in relatively the same direction. This began to change in August 2016 and became noticeable in March of this year. Specifically, more Koreans over the age of 60 favored THAAD while support among other age groups remained more or less the same or fluctuated by no more than 5 percentage points. 73% of Koreans aged 60 and older supported THAAD in March 2017, a significant jump from last November when 58.6% approved. The percentage of disapproval also dropped the most for this group. In November of last year, 26.5% of them disapproved of THAAD which dropped even further, to 13.9%, this March. Koreans in their 50s were second in terms of their support for THAAD. 56% approved while 32.5% disapproved. Their numbers were relatively similar to last November’s. The biggest resistance to THAAD came from Koreans in their 30s. Only 32.9% of them approved while 59.2% disapproved. This was the only group whose support declined from last November, even though the decline was within the margin of error. Following them were Koreans in their 40s, with 40.3% approving and 48.2% disapproving the deployment of THAAD. For Koreans in their 20s, the approval (44.3%) and disapproval (42.9%) rates were within the margin of error, slightly in favor of THAAD.

Figure 7. Public Opinion on THAAD, by Age (%)15

The major reason behind the growing support for THAAD among Koreans aged 60 and older has much to do with their support for President Park. Her favorability rating among Koreans diverged according to whether they approved or disapproved of THAAD. Those who approved of THAAD gave her a favorability score of 2.93 while THAAD critics gave her a score of 0.69. These numbers were statistically significant. Even with President Park removed from office, there is still a significant number of older Koreans who support former President Park, and they have been leading the support for THAAD.16 One thing to keep in mind, however, is that this same age group has previously shown a tendency to change their views depending on the domestic situation. Given that the impeachment proceeding has come to an end and that a presidential election looms in the horizon, we must continue to pay close attention to how the reaction of these older Koreans will impact the support for THAAD.

Table 1. Favorability of President Park according to THAAD Approval/Disapproval17


THAAD, ROK-U.S., and ROK-China Relations

We also found that opinion on THAAD has much to do with favorability of the U.S. and China.18 Supporters of THAAD viewed the U.S. more favorably (6.55) than average (5.71) while those who opposed THAAD viewed the U.S. less favorably (4.72).19 The same could be said about China. The favorability rating of China among Koreans who supported THAAD was 2.85. Those who opposed gave China a much higher score of 3.58 although this was significantly lower than China’s past ratings. This implies that China’s economic retaliation against Korea over THAAD has negatively affected Koreans’ perception of China regardless of their support for THAAD. Once again, this was an adverse reaction to China interfering in what Koreans consider to be their country’s security decision.

Table 2. Favorability of the U.S. and China according to THAAD Approval/Disapproval20


We examined Koreans’ views of THAAD in correlation with their opinion on the nature of Korea’s relationships with the U.S. and China. Accordingly, the United States was still an important cooperative partner for Korea, regardless of THAAD. 90.4% of THAAD supporters answered that the U.S. was a cooperative partner and 82.6% of those who opposed THAAD also said the same. In the case of China, the reverse held true. 63.2% of THAAD supporters saw ROK-China relations as competitive and more than half (52.7%) of THAAD detractors answered the same. Regardless of Koreans’ opinion on THAAD, China’s negative economic retaliation resulted in bringing them together and instilling an impression that Korea’s relationship with China was competitive.

Table 3. Nature of Korea’s Relationships with the U.S. and China according to THAAD Approval/Disapproval21



Korea’s domestic and external situations are undergoing profound changes. Domestically, President Park was removed from office, and there will be an early presidential election in May. Externally, Korea finds itself stuck between the United States pushing for an early deployment of THAAD and China continuing its economic retaliation against Korea. This has resulted in Korean companies located in China and Korean cultural exports bearing the brunt of the damage.

Koreans’ opinion on THAAD appears to be influenced by Korea’s domestic situation. Specifically, President Park’s impeachment and public distrust of her administration appear to be influencing how Koreans view the issue of THAAD. As a result, young Koreans, who are critical of President Park, see THAAD negatively despite their conservative views on national security. On the other hand, older Koreans, who are more favorable toward President Park, support THAAD more than their younger compatriots.

This has had a noticeable impact on how Koreans see their neighbors, particularly the United States and China. Most notably, their favorability of China has declined precipitously, regardless of their opinion on THAAD. While this change was visible across all age groups, it was most pronounced among older Koreans. Even among younger Koreans who opposed THAAD, Chinese retaliation was not viewed favorably. In the end, this has influenced how Koreans see their country’s relationship with China. More than half of Koreans now see the two countries’ relationship as being competitive rather than cooperative. Once again, this holds true regardless of their opinion on THAAD.

Despite the growing support for THAAD and declining popularity of China among Koreans, the United States cannot afford to lower its guard. Older conservative Koreans have been the driving force behind growing support for THAAD and steady favorability of the United States. However, it appears that their support has much to do with Korea’s domestic situation. This is especially important given that they were waving the American flag and voicing their support of the U.S. during their protests against President Park’s impeachment. The U.S. should pay more attention to the fact that America’s favorability rating dropped to around 4 among Koreans in their 40s, and that a similar tendency was observed among Koreans in their 20s, who have in the past been a staunch proponent of the United States. President Trump’s low favorability may also work against the United States moving forward.

There is much uncertainty as Korea prepares to elect a new president. Moreover, former President Park’s criminal prosecution will only add noise and tension domestically. In a way, THAAD is an issue that is being brought up in the wrong place at the wrong time. Regardless of whether THAAD is deployed or not, it will likely influence Korean public opinion toward the United States and China in the long run. Korea’s deteriorating relationship with China is especially worrisome. Given the importance of public diplomacy, especially for superpowers such as the United States and China, any change in Korean public opinion will be important. As such, both the United States and China will need to identify changes taking place and make the appropriate adjustments to maintain and/or improve relations with Korea.


– Sample size: 1,000 respondents over the age of 19
– Margin of error: +3.1% at the 95% confidence level
– Survey method: Random Digit Dialing (RDD) for mobile and landline telephones Computer-Assisted Telephone Interviewing (CATI)
– Period: See footnote of each figure/table
– Organization: Research & Research

The views expressed herein do not necessarily reflect the views of the Asan Institute for Policy Studies.

  • 1.

    Special thanks to Mr. Benjamin Forney for his comments.

  • 2.

    At the time, China’s favorability ratings were quickly catching up with the United States’. China’s numbers were 5.46 in September, 5.41 in October, and 5.54 (highest) in November.

  • 3.

    Asan’s regular survey (Date: January 2016-March 2017).

  • 4.

    When we examined China’s favorability numbers from the past, Koreans in their 50s were more favorable toward China than Koreans younger than 40. Also, the favorability numbers among Koreans younger than 40 ranged from 3-5, while numbers for Koreans over the age of 50 were more diverse (2-6).

  • 5.

    Asan’s regular survey (Date: January 2-4, 2017; March 6-8, 2017).

  • 6.

    Favorability ratings for the U.S. in January 2017 were as follows: 5.59 (20s), 5.53 (30s), 5.32 (40s), 5.75 (50s), 6.56 (60+). In March, the numbers were 5.54 (20s), 5.45 (30s), 4.76 (40s), 5.67 (50s), and 6.96 (60+). Only Koreans over the age of 60 had a higher number than before.

  • 7.

    Asan’s regular survey (Date: January 2016-March 2017).

  • 8.

    President Xi’s favorability was still higher than Prime Minister Abe’s. Prime Minister Abe’s favorability dropped from 2.03 in January to 1.56 in March. His lowest rating in 2016 was 1.65 (highest 1.93).

  • 9.

    Asan’s regular survey (Date: August 2016-March 2017).

  • 10.

    Country and leadership favorability ratings in July 2016 were measured between July 1-3. Therefore, the impact of the ROK-US THAAD agreement (July 8) was not accounted for in the July survey.

  • 11.

    Asan’s regular surveys (Date: August 2016-March 2017).

  • 12.

    See “A Shrimp Between Two Whales? Koreans’ View of the US-China Rivalry and THAAD,” (Kim Jiyoon, John J. Lee, and Kang Chungku, 2017) for more information on changing public opinion toward THAAD.

  • 13.

    Asan’s regular and special survey (Date: March 18-20, 2015; February 10-12, 2016; August 16-18, 2016; September 21-23, 2016; November 22-24, 2016; and March 6-8, 2017).

  • 14.

    Following them were Koreans in their 40s (November 2016: 59.1% -> March 2017: 48.2%) and 20s (November 2016: 52.6% -> March 2017: 42.9%).

  • 15.

    Asan’s regular and special survey (Date: March 18-20, 2015; February 10-12, 2016; August 16-18, 2016; September 21-23, 2016; November 22-24, 2016; and March 6-8, 2017).

  • 16.

    Former President Park’s favorability was highest among Koreans aged 60 and older (3.72), followed by those in their 50s (2.30). Others were significantly less favorable toward her (20s: 1.00; 30s: 0.96; 40s: 1.42).

  • 17.

    Asan’s regular survey (Date: March 6-8, 2017). Using the t-test, we compared the average scores of former President Park’s favorability in March 2017 according to whether they supported/opposed THAAD. Answers of “don’t know/refused” were calculated as “missing.”

  • 18.

    Using the t-test, we compared the average scores of country favorability in March 2017 according to whether they supported/opposed THAAD. Answers of “don’t know/refused” were calculated as “missing.”

  • 19.

    However, since the support rate for THAAD was higher, it did not have much influence on the overall country favorability rating.

  • 20.

    Asan’s regular survey (Date: March 6-8, 2017).

  • 21.

    Asan’s regular survey (March 6-8, 2017). By cross-analysis, we compared the favorability toward ROK-U.S. and ROK-China relations according to whether they supported/opposed THAAD. Answers of “don’t know/refused” were calculated as “missing.”


About Experts

Kim Jiyoon
Kim Jiyoon

Research Division

Dr. KIM Jiyoon is a senior fellow in the Public Opinion Studies Program at the Asan Institute for Policy Studies. Previously, Dr. Kim was a postdoctoral research fellow at Université de Montréal. Her research interests include elections and voting behavior, American politics, and political methodology. Her recent publications include “Political judgment, perceptions of facts, and partisan effects” (Electoral Studies, 2010), “Public spending, public deficits, and government coalition” (Political Studies, 2010), and “The Party System in Korea and Identity Politics” (in Larry Diamond and Shin Giwook Eds., New Challenges for Maturing Democracies in Korea and Taiwan, Stanford University Press, 2014). She received her B.A. from Yonsei University, M.P.P. in public policy from the University of California, Berkeley, and Ph.D. in political science from the Massachusetts Institute of Technology.

John J. Lee
John J. Lee

Research Division

John J. Lee is a senior associate at the Asan Institute for Policy Studies. Mr. Lee is also a member of the Young Leaders Program at Pacific Forum CSIS. His research interests include Northeast Asian security, US foreign policy, political issues related to North Korea, and economic sanctions. He received his B.A. in Government from Dartmouth College and M.A. in International Studies from Yonsei University Graduate School of International Studies (GSIS).

Kang Chungku
Kang Chungku

Public Opinion Studies Team

Mr. Kang Chungku is a principal research associate working on public opinion surveys and data analysis at the Asan Institute for Policy Studies. Mr. Kang has led the Asan Institute’s Annual Survey series, “South Koreans and Their Neighbors,” for the past decade and he also undertakes regular surveys into key foreign policy issues facing South Korea. He also supports the Institute’s researchers with quantitative data analysis. Prior to joining the Asan Institute, he was a research assistant at the Korea Dialogue Academy in Seoul. His research interests include quantitative research methods, survey design, and statistical data analysis. Mr. Kang received his B.A. in English and M.A. in Sociology at Korea University.