The American Public Remains Committed to Defending South Korea

October 1, 2018

By: Karl Friedhoff, Fellow, Public Opinion and Asia Policy

South Korea’s Moon Jae-in and North Korea’s Kim Jong Un met in Pyongyang from September 18-20 for their third summit in less than 12 months. The two leaders discussed the next steps toward North Korea’s potential denuclearization, economic cooperation and aid to North Korea, and formally ending the Korean War. As President Donald Trump and Kim Jong Un make plans for a possible second summit, tensions have eased significantly from one year ago. But little tangible progress has been made on the denuclearization of North Korea.

The 2018 Chicago Council Survey finds that the US public views North Korea’s nuclear program as one of the top threats facing the country despite the recent cooling in tensions. Greater than eight in ten Americans reject the idea that North Korea should be allowed to produce nuclear weapons. While Americans broadly support sanctions against North Korea if it does not denuclearize, there is little appetite for military action to forcibly denuclearize North Korea.

North Korea Remains a Top Threat

In 2018, the tensions between the United States and North Korea receded from their 2017 highs after Trump surprised the world by agreeing to meet with Kim in Singapore in June. That easing of tensions is reflected in American public opinion. Six in ten Americans (59%) now say that North Korea’s nuclear program is a critical threat facing the United States, down from the all-time high in 2017 when it was 75 percent. Even so, the North’s nuclear program is the second-ranked potential threat included in the survey, trailing only international terrorism (66%).

Americans Support Allies against North Korean Aggression

While Americans perceive North Korea’s nuclear program as less of a threat to the United States than last year, if North Korea were to attack either South Korea or Japan, bipartisan majorities of Americans are ready to use force to defend these countries. If North Korea invades South Korea, 64 percent of Americans support sending US troops to defend South Korea. This is an all-time high and includes 70 percent of Republicans, 63 percent of Democrats, and 61 percent of Independents. Likewise, if North Korea attacks Japan, 64 percent support using US troops to defend Japan. This is also a record high, including 70 percent of Republicans, 62 percent of Democrats, and 63 percent of Independents.

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If North Korea were to attack a US military base in the Pacific, support for the use of US troops is even higher. More than eight in ten (84%) support the use of US troops to respond. Those numbers are consistent across parties.

Of course, the United States has multiple long-term bases spread across the Pacific, including in South Korea and Japan. Support for bases in both countries is also at a new high. Three-quarters of Americans support maintaining long-term bases in South Korea (74%) and more than six in ten (65%) say the same about bases in Japan.

Policy Options on North Korea

There are few good policy options when it comes to dealing with North Korea, and no previous administration has convinced North Korea to abandon its nuclear and missile programs. If North Korea were to denuclearize, the American public supports a range of concessions. If it does not denuclearize, the American public sees limited options for the United States.

The American public supports a range of steps on the part of the United States if North Korea were to denuclearize. Three-quarters of Americans (77%) support establishing diplomatic relations with North Korea should they give up their nuclear weapons, and majorities favor providing economic and humanitarian aid to North Korea (54%). A similar majority supports the partial withdrawal of US troops from South Korea (54%). However, only a minority favor cancelling US-ROK military exercises (44%), and fewer than two in ten (18%) support a complete withdrawal of US troops from South Korea. Each of these results is consistent across parties.

The more difficult scenario arises if North Korea does not denuclearize—an outcome that currently seems the more likely. If this is indeed the case, the American public only sees one viable option—to impose tighter economic sanctions on North Korea, with 77 percent support. Airstrikes on the North’s nuclear facilities (37%) and accepting that North Korea will possess nuclear weapons in exchange for an agreement guaranteeing it will not produce more of them (29%) receive only minority support. Doing nothing is the least popular option—just 13 percent say the United States should accept that North Korea will possess and produce additional nuclear weapons.

Little Support for Military Action against North Korea

Military action carries with it the very real risk of retaliation and escalation, and as in past surveys, lacks public support. Overall, 25 percent of Americans favor sending US troops to overthrow the Kim Jong Un regime if North Korea does not denuclearize. Fewer than four in ten (37%) favor conducting airstrikes against North Korea's nuclear production facilities. Such airstrikes against the North’s nuclear facilities are the only option that elicits a clear partisan divide. A majority of Republicans (55%) support such airstrikes versus 29 percent of Democrats and 34 percent of Independents.

If the United States opted for military action against North Korea, the American public thinks it would be necessary to get the approval of the US Congress. Six in ten (63%) say such approval would be necessary and a further 21 percent say it would be preferable but not necessary. Just 11 percent say it would be neither preferable nor necessary.

But the same is not true for approval of other institutions and governments. Four in ten (43%) say it would be necessary to get the approval of most US allies, 42 percent say the same for the approval of the South Korean government, 41 percent for the approval of the UN Security Council, and just 22 percent for the approval of China.

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No Love Lost for Kim Jong Un

Despite the recent diplomatic makeover attempted by Kim Jong Un, he continues to be the least favored international leader included in the survey. Like in 2017, just 6 percent of Americans report a favorable view of Kim in 2018. Nine in ten (91%) hold unfavorable views of him, with 67 percent holding very unfavorable views. By contrast, a majority (67%) now hold a favorable view of South Korean President Moon Jae-In. This is up 13 percentage points from 2017 when it was 54 percent.


The analysis in this report is based on data from the 2018 Chicago Council Survey of the American public on foreign policy. The 2018 Chicago Council Survey was conducted by GfK Custom Research using their large-scale, nationwide online research panel between July 12 and July 31, 2018 among a representative national sample of 2,046 adults, 18 years of age or older, living in all 50 US states and the District of Columbia. The margin of sampling error for the full sample is ±2.37, including a design effect of 1.1954. The margin of error is higher for partisan subgroups or for partial-sample items.

The 2018 Chicago Council Survey is a project of the Lester Crown Center on US Foreign Policy, and is made possible by the generous support of the John D. and Catherine T. MacArthur Foundation, the Korea Foundation, the US-Japan Foundation, the generous support of the Crown family, and the Robert R. McCormick Foundation.

About the Chicago Council on Global Affairs

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The American Public Remains Committed to Defending South Korea

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