Bridging the Divide in the U.S.-South Korea Alliance

The United States’ alliance with South Korea is one of its most important relationships—not just in Asia but around the world. Yet no alliance is without disagreement, and as the United States and South Korea’s partnership approaches its eighth decade, new geopolitical realities could pose obstacles to its integrity.

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With North Korea continuing to build on its capabilities to produce weapons of mass destruction and China posing growing challenges, it is as important as ever that progressive and conservative policymakers on both sides of the alliance understand one another’s perspectives. Both sides must invest in finding ways to forge consensus on key issues and bridge the divide where necessary. However, they must also realize that it is natural to have different positions and that it is OK to not agree on everything.

In particular, progressive foreign policy leaders in both countries share many perspectives, but their views sometimes differ on two fundamental questions: 1) What are the greatest challenges that the alliance should focus on? and 2) How should the alliance address the threat posed by North Korea?

Based in part on a series of interviews the authors conducted with experts in the two countries, this report provides a window into how progressives in Seoul and Washington view the alliance as 2021 begins. It also makes recommendations as to how both countries can advance shared interests in the coming year as the new U.S. administration takes office. While this report explores the alliance overall, it focuses in particular on the perspectives of progressive leaders and their impacts on the alliance.

Over the past four years, U.S. President Donald Trump’s disdain for the U.S.-South Korea alliance has undermined the partnership, causing a wide gap in trust between the two sides. During his time in office, Trump has made clear that he does not understand the value of U.S. alliances. He has suggested that allies such as South Korea and Japan protect themselves by developing their own nuclear weapons. Furthermore, he essentially tried to extort U.S. allies—most notably South Korea—by threatening to withdraw U.S. troops from the country unless Seoul began paying “a lot more” for U.S. defense. This position ignores the fact that America, not just its allies, benefits from its military presence in Asia.

The Trump administration continued its transactional approach to alliances during cost-sharing negotiations with Seoul. In 2018, upon the expiration of the Special Measures Agreement (SMA), the administration demanded a 150 percent increase—$1.2 billion annually—to sustain the U.S. military presence on the Korean Peninsula. Seoul fended off such demands by offering an 8.2 percent increase and a shorter expiration date for the SMA, and the allies agreed to renegotiate the agreement annually with incremental increases. But when the agreement expired again at the end of 2019, the Trump administration demanded a whopping 500 percent increase in contributions. Negotiations dragged on for months, causing thousands of United States Forces Korea (USFK) workers to be placed on unpaid leave. Ignoring the fact that South Korea paid 90 percent of the $11 billion construction cost for Camp Humphreys—the largest U.S. overseas military base—and is a major customer of U.S. defense companies, the Trump administration shot down Seoul’s best offer of 13 percent and has yet to define what a “fair and equitable” cost-sharing agreement would look like.

Trump has treated South Korea like a lesser partner and has bullied Seoul on a wide range of economic, security, and military issues. Searching for a political win in 2017, he inaccurately claimed that the United States-Korea Free Trade Agreement (KORUS FTA) was responsible for lost U.S. jobs; and he essentially forced Seoul to renegotiate by threatening to withdraw from the agreement. Convinced that a trade deficit between the two countries was detrimental to U.S. interests, Trump continued to penalize Seoul by levying tariffs on major South Korean exports. Furthermore, Trump’s destructive trade war with China caused South Korean exports to China, its biggest trading partner, to fall by 21.3 percent in 2019.

The Trump administration’s shoddy treatment of South Korea has damaged America’s standing with South Koreans. While 92 percent of the South Korean public remains supportive of the alliance, public perception of the United States has fallen to an almost historic low of 45 percent. Only 4 percent of South Koreans supported paying billions of dollars more in cost-sharing negotiations, and a recent poll measured South Koreans’ confidence in President Trump at an abysmal 17 percent.

Despite the Trump administration’s tumultuous policies, the U.S.-South Korea alliance has survived, in large part due to President Moon Jae-in’s efforts. South Korea could have easily levied tariffs on U.S. goods in response to Trump’s trade war. Instead, Moon agreed to renegotiate the KORUS FTA. When Trump pledged in 2018 to cancel joint military exercises without prior consultation, the Moon administration quietly scrambled to adjust to Trump’s stance. Instead of decrying Trump’s unreasonable SMA demands, the Blue House has consistently downplayed the issue and insisted that both sides are deepening “mutual understanding” as negotiations continue. Other officials within the U.S. government have similarly attempted to play down the disagreements being fueled by Trump.

And despite all the insults Trump has thrown at South Korea—reportedly calling South Koreans “terrible people,” questioning South Korea’s laudable COVID-19 response, and mocking historic South Korean Academy Awards wins on Twitter—President Moon sent the United States 2 million face masks and sent Maryland 500,000 COVID-19 tests as Trump left the responsibility of coronavirus testing to the states.

The Moon administration has sought to conceal the rifts in the alliance in part because it needs U.S. support for its peace initiative with North Korea. North Korea wants sanctions relief and security guarantees—concessions that Seoul cannot provide without U.S. support. Moon has made advancing inter-Korean relations his chief foreign policy initiative, and much of his legacy will depend on whether he can successfully deliver on those promises. Thus, Moon has sought to downplay disagreements and accommodate Trump when possible in the hopes of keeping U.S. engagement with Pyongyang alive.

But Moon’s vocal support for Trump’s North Korea diplomacy has not been able to overcome the long-standing discrepancy in views between the United States and many progressives in South Korea: Many in Seoul believe that sanctions relief for the Democratic People’s Republic of Korea (DPRK) should happen as part of confidence-building measures, while the Trump administration and others in Washington believe that sanctions relief is important leverage, only to be offered with significant progress along the path to denuclearization. At the same time, the United States and South Korea have often seemed uncoordinated in their approaches to North Korea, sometimes outright accusing each other of taking steps without prior consultation.

This was the obstacle that Trump and Kim could not clear at their Hanoi summit in February 2019. Trump walked away from Kim Jong Un’s offer to dismantle the nuclear facilities at Yongbyon in exchange for partial sanctions relief, embarrassing Kim by cutting the summit short and leaving him with nothing to show for a 65-hour train ride there. Despite Trump and Kim meeting for another short summit at the Demilitarized Zone (DMZ) in the summer of 2019, as well as subsequent working-level talks, substantive diplomacy has not moved forward since.

Since then, neither the United States nor North Korea have appeared to be interested in resuming talks. After the last round of U.S.-DPRK working-level talks broke down in Stockholm on October 5, 2019, the Moon administration kicked off 2020 with proposals to continue advancing inter-Korean relations through economic cooperation, putting forth ideas such as resuming individual tours to the North and initiating barter-trade agreements. In response to Moon’s proposals, the U.S. ambassador to South Korea, Harry Harris, insisted that Seoul should consult with the United States on any measures before proposing them, especially since the tourism initiative could spur incidental sanctions violations. North Korea has continuously rebuffed South Korean outreach efforts and even physically destroyed the inter-Korean liaison office in June 2020. Although the office had been closed due to the coronavirus pandemic, it was a tangible achievement of Moon’s peace efforts and served as an official channel to enhance communication between the two countries.

Despite these setbacks, President Moon continues to prioritize reviving diplomacy with North Korea—most recently signaled with his new Cabinet appointments and his 2020 U.N. speech in which he advocated for the formal end of the Korean War. The chances for diplomacy in 2021 seem to rest largely on whether North Korea and the United States are interested in resuming talks.

The U.S.-South Korea alliance, of course, is just one component of the broader foreign policy conversations happening in each country. As U.S. progressives survey the world, they see an array of growing challenges, from climate change to pandemics to the rise of authoritarianism and illiberalism. They believe that cooperation among the world’s democracies—driven by shared values—must be at the core of any solution to these problems. U.S. progressives see South Korea as one of the key partners for upholding this vision.

The U.S.-South Korea alliance—and America’s views on it—have changed considerably over its 70-year lifespan. At the end of the Korean War, the Republic of Korea (ROK) was one of the poorest countries in the world, and the alliance served to defend it against potential North Korean attacks. Although both Koreas had similar starting points, South Korea’s gross domestic product (GDP) per capita is now 54 times larger than that of North Korea. Despite this drastic change in South Korea’s prosperity and its elevated geopolitical position—now a member of the G-20 and a key player on a wide range of regional and global issues—the alliance’s focus has remained overwhelmingly on the threat from North Korea.

North Korea

When it comes to North Korea, opinions within the U.S. progressive foreign policy community fall on a wide spectrum, ranging from support for engagement without preconditions to support for more pressure over North Korea’s weapons of mass destruction (WMD) programs and human rights record. While U.S. progressives are traditionally more likely than their conservative U.S. counterparts to support diplomacy with North Korea, many are still wary of what engagement can achieve, in no small part chastened by previous diplomatic failures and North Korea’s attempts to cheat on past agreements. Furthermore, some progressives—who often see the United States as a standard-bearer for supporting human rights and nonproliferation—believe that engagement with North Korea must be balanced against the interests of not appearing to reward a regime that flouts the most basic international norms.

Some U.S. progressives support a step-by-step approach that includes confidence-building measures to help build momentum for a process that—while it may produce denuclearization somewhere down the road—is unlikely to see North Korea give up all of its WMD programs quickly. Some progressives believe the United States should take steps, such as declaring an end to the Korean War and considering a peace treaty, to send a signal to North Korea about the United States’ commitment to diplomacy. Others believe that North Korea must take the first steps to show that it is serious about denuclearization before a genuine step-by-step diplomatic process can begin. These balancing interests and perspectives among progressives in the United States often result in a complicated and nuanced approach to the question of how best to conduct diplomacy with North Korea.

Regional and global issues

Beyond North Korea, many U.S. progressives believe that South Korea should play a bigger role in regional and global affairs. South Korea is one of the few countries that went from being a recipient of development assistance to a donor of its own. It has transitioned from an autocracy to a flourishing democracy. It has made great strides in education and economic development and set an example for the world with its COVID-19 response. U.S. progressives see much potential for the U.S.-South Korea alliance to play a meaningful role on a broad range of issues, from promoting sustainable development to cooperating on cyber issues to responding to global humanitarian needs and beyond.

Seoul’s interest in meeting these expectations can vary depending on whether progressives or conservatives are in power. South Korean conservatives are more likely to welcome the idea of becoming a well-established middle power, while South Korean progressives believe the North Korean security challenge must take priority. U.S. progressives perceive the alliance as fully capable of doing both and want to see the U.S.-South Korea alliance working toward a wider set of shared interests and values.

As part of U.S. progressives’ vision to unite democratic allies, they see space for Japan and South Korea to work together. The two countries are both economic powerhouses that face similar security concerns and are close allies of the United States. U.S. progressives perceive the two countries as important partners in their regional strategy and believe that cooperation should be expanded, despite often strained ties between the two.

China

U.S. progressives also view rising U.S.-China tensions as a competition of values and as a key concern for the U.S.-South Korea alliance. In recent years, China’s actions have sparked growing worries in the United States. China has perpetrated a vast incarceration of Uighur Muslims, cracked down violently on pro-democracy movements in Hong Kong, and militarized outposts in the South China Sea, among a variety of other concerning actions. With its destabilizing behavior, many policymakers across the political spectrum in the United States increasingly view China as a top challenge.

Trump has pursued an erratic China policy that has veered wildly between courting President Xi Jinping and confronting China with pressure. According to one study, Trump’s trade war with China cost the U.S. economy $1.7 trillion. And while in 2020, the Trump administration has taken a series of actions against China on everything from Hong Kong to technology companies to Uighur Muslims, its strategy and goals have been unclear.

U.S. progressives believe that Trump’s China policies have been ineffective and counterproductive and that, more broadly, Trump’s America-first policies have weakened the United States on the world stage, thereby opening up more opportunities for China to gain influence. In particular, Trump’s antagonistic relationship with allies—including the targeting of allies such as South Korea as part of his trade war—has prevented the United States from working with partners to address the threats that China poses. U.S. progressives see democratic allies such as South Korea as a critical part of responding to China’s increasingly concerning behavior.

Many of the Trump administration’s policies over the past few years have undermined the alliance and angered progressive leaders in Seoul. But Trump’s decision to engage directly with Kim Jong Un was popular among South Korean progressives and helped to conceal rifts in the alliance.

North Korea

With South Korean President Moon Jae-in staking his legacy on outreach to the North, over the past few years Seoul has prioritized gaining Washington’s support for diplomacy with North Korea. South Korean progressives traditionally tend to be much more forward-leaning with the DPRK. They are willing to actively pursue steps such as joint economic projects and humanitarian assistance as confidence-building measures, while simultaneously addressing threat reduction and denuclearization.

Moon’s predecessors have tried to negotiate with North Korea but have not always found a willing partner in Washington—or, of course, in Pyongyang. Even now, Washington remains much more skeptical about Kim Jong Un’s intentions given the long history of failed negotiations with the North. Nevertheless, most South Korean progressives contend that Kim Jong Un was serious about reducing tensions and improving relations in the most recent round of diplomacy. They assert that economic prosperity plays a bigger role in Kim’s legitimacy and point to his speeches promising economic development. Some even insist that the country’s expanding market economy and black market have increased the flow of information in the country, increasing North Korean awareness of the outside world and challenging state depictions of the country and regime—as well as pressuring Kim to provide a better living standard for his people.

Others predict that Kim may have been motivated to pursue stronger relations with the United States and South Korea to balance against Chinese geopolitical influence. South Korean progressives point to the length of time in which Kim was engaged in diplomacy with Seoul and Washington as a sign of Kim’s intent to improve relations. While Pyongyang has issued statements critical of South Korea, progressives in Seoul maintain that Kim Jong Un has been careful not to cross any red lines, such as intercontinental ballistic missile (ICBM) testing, in the hopes of keeping diplomacy alive.

Instead, South Korean progressives increasingly view the United States as the obstacle to advancing inter-Korean relations. Despite support for Trump’s attempt at diplomacy, they are frustrated that negotiations remain deadlocked and perceive Washington’s hard-line approach to sanctions as the main cause. Some even advocate for a rebalancing of the U.S.-South Korea alliance away from what they perceive as dependence on the United States, as they feel that their interests are not being heard and that South Korea’s autonomy is being eroded.

While South Korean progressives perceive U.S. progressives as more likely than the Trump administration to treat South Korea like true equals when it comes to issues such as cost-sharing negotiations, they also view some U.S. progressives as too wary of engagement with North Korea and too critical of Kim Jong Un’s intentions to reduce tensions. South Korean progressives assert that the United States often sets the bar for diplomacy too high. They contend that denuclearization should be a long-term goal and that tangible progress toward denuclearization cannot happen without painstaking efforts to relieve the 70 years of hostility and tension between the United States and the DPRK.

South Korean progressives largely perceive the Obama administration’s “strategic patience” approach as lost time—a period when the United States tried to add pressure to North Korea without making serious attempts at diplomacy. While Trump’s treatment of South Korea angered many across the political spectrum, many South Korean progressives supported Trump’s willingness to start high-level diplomacy with North Korea.

But as U.S.-China tensions increase, South Korean progressives fear that Chinese cooperation on North Korea will be jeopardized. Since it accounts for more than 90 percent of North Korea’s trade, China is especially instrumental to enforcing sanctions against the Kim regime. As a bipartisan consensus emerges from Washington that a tougher approach to China is necessary, many South Korean progressives are concerned that denuclearization and peace on the Korean Peninsula will become less of a priority.

China

This divergence in how Seoul and Washington view China is a growing issue in the alliance, and the decision to deploy the Terminal High Altitude Area Defense (THAAD) system in South Korea is a good illustration of how the divergence in opinions is playing out. The Center for American Progress noted in its 2019 report the importance of this issue in shaping perspectives in South Korea, and it remains even more relevant today.

In 2016, after continual missile testing from the North, U.S. President Barack Obama and South Korean President Park Geun-hye agreed to deploy the THAAD system to strengthen South Korea’s defense against North Korean missiles. However, Chinese Foreign Minister Wang Yi expressed concern that THAAD deployment would jeopardize China’s “legitimate national security interests,” and Beijing quickly sought to use its economic clout to pressure Seoul to reverse its decision. Through unofficial boycotts of South Korean goods and a virtual clampdown on Chinese tourism to the ROK, Beijing inflicted a $7.5 billion loss to the South Korean economy in 2017.

South Korean progressives viewed the economic coercion as an infringement upon South Korea’s sovereignty and national security, and the incident displayed the dangers of economic interdependence with China. But in the eyes of some South Korean progressive policymakers, the United States had failed to do enough to support its ally in its time of need. The United States and South Korea both made an alliance decision to deploy THAAD as a deterrent against North Korea’s missile program and for the stability of the broader region. As South Korea bore Beijing’s wrath, South Korean progressives felt that the U.S. response was lacking.

U.S. progressives had mixed reactions to this perspective: Some agreed that the United States had let South Korea down and that it should find ways to help South Korea and other partners build systems of economic resilience against these types of threats and actions. Others pointed out that it was difficult for the U.S. government to respond, as China’s retaliation did not take place at a state level.

While South Korean public opinion of China fell and has continued to decrease since Beijing’s economic coercion over THAAD, the perception of the United States has fallen across the world as Trump has withdrawn the United States from its traditional role as a world leader. Recent polling from the Asan Institute for Policy Studies notes that both the United States and China hit record-low favorability ratings in South Korea; but when presented as a binary choice, the South Korean public drastically favored the United States to China.

South Korean progressives also prefer to work with the United States over China as the two allies share common values and interests. While South Korean progressives share many concerns with U.S. policy leaders regarding China, the THAAD experience was a clear reminder of how susceptible Seoul is to pressure from Beijing. South Korean progressives worry that the increasing U.S.-China competition will threaten their national interests and wish to see Washington take a more balanced approach to China.

U.S.-South Korea-Japan relations

As the United States seeks to align its democratic allies to pressure China, South Korean progressives find U.S. efforts to enhance U.S.-South Korea-Japan trilateral cooperation extremely uncomfortable. While Washington argues that Japan and South Korea share similar security threats from North Korea and the same values, some South Korean progressives view these efforts as forcing the two countries to get along for the sake of U.S.-China strategic competition.

South Korea and Japan have an unresolved colonial past that bleeds into their economic and security cooperation. Believing that these historical issues hindered meaningful cooperation between the two countries, the United States urged Japan and South Korea to sign an agreement covering the “comfort women” issue in 2015. With the nudge of U.S. officials, the two countries then signed the General Security of Military Information Agreement (GSOMIA), an intelligence-sharing agreement.

However, there is great resentment among South Korean progressives toward President Obama for this chain of events. South Korean progressive experts lamented that they had to come to terms with a deep and painful historical issue at the insistence of another country. The term “comfort women” refers to an estimated 200,000 women, mostly Korean, who were forced into Japanese military-run brothels during World War II. The comfort women agreement was not something widely supported by South Korean progressives and remains unpopular among the South Korean public. South Korean progressives, who traditionally advocate for a more independent foreign policy, have criticized former President Park Geun-hye, who signed both agreements, for supposedly putting U.S. interests first. President Park’s impeachment and removal from office based on charges of corruption further tarnished the agreement in the eyes of the South Korean public.

Moreover, when Japan economically retaliated against South Korea’s court ruling on forced labor during the colonial era, South Korean progressives felt discriminated against, as the Trump administration intervened only when Seoul threatened to terminate GSOMIA. South Korean progressives believed that Tokyo initiated the conflict by restricting access to materials critical to South Korea’s semiconductor industry and maintained that military information sharing with Japan regarding North Korean threats would have continued even without GSOMIA. When the Trump administration responded by opposing South Korea’s decision and imploring Seoul to continue GSOMIA, some South Korean progressives believed that this was because Washington wanted South Korea and Japan to share information regarding China’s military activities.

This narrative of how the United States is supposedly pulling South Korea into the middle of a U.S.-China strategic competition arises in other parts of the alliance as well. Some South Korean progressives contend that the United States is stalling on operational control (OPCON) transfer conditions because it does not want to return operational wartime control to Seoul during rising tensions with China. And while South Korean progressives remain open to reducing the number of USFK troops in support of diplomacy with North Korea, most American policymakers believe that troops should not be altered as they are a symbol of commitment to the U.S.-South Korea alliance and such a withdrawal would signal a retreat from the region to Beijing.

While not all of these are commonly held beliefs, the overarching narrative is there: While South Korean progressives are largely supportive of America and the alliance, many feel that their interests are not being heard and that they are but a chess piece in U.S.-China strategic competition. 

As 2021 begins, both the United States and South Korea—including progressives on both sides—have work to do to strengthen the alliance and bridge the trust divide. Over the next year, the alliance should focus on a handful of concrete policy initiatives that can advance shared interests, while also addressing some of the underlying disagreements identified above.

North Korea

Create a joint U.S.-South Korea road map for diplomacy with North Korea

The United States and South Korea should create a road map for an allied approach to diplomacy with North Korea. Trump’s surprise move to begin diplomacy with North Korea—at the summit level no less—made it difficult for the United States and South Korea to hammer out an agreed path forward first, which allowed North Korea to exploit the tensions in the alliance. For example, the Moon administration supported an end of war declaration as a way to boost peace efforts, while the Trump administration clearly did not agree. Similarly, the United States was wary of Moon’s announcement of economic projects with North Korea and his moves to reduce military activities in the DMZ, which some in the United States believe was done without full advance consultation with Washington.

Outlining key milestones for the way forward would help relieve tensions and manage expectations between the two allies, present a united posture toward North Korea, and make diplomacy far more likely to yield progress. This road map should include an agreement on the types of concessions and demands—such as the terms for an end of war declaration—as well as a consensus on how to sequence the process of talks and short- and long-term goals for both parties. All of these decisions must, of course, consider the commitments that South Korea has already made to North Korea in the Panmunjom and Pyongyang Declarations.

The United States should open a more senior, regular communication channel with North Korea

The United States should seek to establish a regular channel of engagement with North Korea—beyond the New York channel available through the United Nations—which should include a new liaison office if circumstances permit it. This measure should not be a concession, but rather part of a renewed outreach effort and a signal of America’s commitment to more sustained diplomatic engagement to advance U.S. interests. Improving formal communication between both sides is an important first step toward achieving U.S.-South Korea alliance goals of peace and stability on the Korean Peninsula. The opening of liaison offices was one of the items reportedly ready to be announced as part of the agreement that was almost reached in Hanoi, indicating that it is possible to achieve and likely has support from constituencies within both governments.

Opening an actual liaison office quickly might be difficult: Amid the pandemic, North Korea has cut off most foreign contact and sent many diplomats home; Pyongyang also blew up the existing inter-Korean liaison office in an attempt to express anger at the inability of the diplomatic process to yield the results it wanted. Nevertheless, making clear at the outset that the United States wants a higher-level regular channel of communication is a worthwhile step that would at the very least send a signal about America’s interest in ongoing diplomatic engagement.

The United States and South Korea should work together to provide COVID-19 assistance to North Korea

The alliance should step up multilateral assistance to programs and institutions that are already operating in North Korea to address challenges exacerbated by COVID-19. As the DPRK-China border currently remains closed as a prevention measure against COVID-19, North Korea experienced its wettest monsoon season in 40 years, contributing to a reduced crop yield in an already food-insecure country. The United States and South Korea must work together to provide humanitarian assistance—as the morally right thing to do and as a signal of goodwill toward Pyongyang. If successful, this initiative could eventually be broadened into a dialogue with the DPRK and other regional partners on pandemic response and public health, an idea that President Moon proposed during his U.N. speech in September.

Regional and global affairs

As the United States and South Korea hold somewhat divergent views on how much of a role the alliance should play in regional and global issues beyond the peninsula, 2021 would be a good time to try a new initiative that could meet the expectations of both countries. By working with South Korea on the global response to the pandemic, the United States could help bolster the alliance’s ability to focus on global issues while choosing an issue that South Korea has already been contributing to beyond its borders. To start, the two allies should establish a series of priorities for the alliance to tackle in terms of building public health capacity—such as strengthening the World Health Organization (WHO), ensuring fair vaccine distribution, sharing pandemic-related lessons, and providing public health assistance to developing countries. Initial steps could include becoming members of the WHO’s Access to COVID-19 Tools (ACT) Accelerator, a global collaboration dedicated to the accelerated development and production of, as well as equitable global access to, COVID-19 tools. South Korea’s effective response to the pandemic remains a model around the world; combined with America’s resources and expertise, the two countries could help bolster the international response.

China

China looms large over many aspects of the U.S.-South Korea alliance, whether it is North Korea or force posture or economic relations. The first step that the United States needs to take is to formulate and articulate a clear, comprehensive China strategy. While perhaps a relatively obvious task, over the past few years the United States has lacked a coordinated and consistent approach, which is part of the reason that U.S. policy toward China has caused friction in the alliance with South Korea. As a part of developing a strategy, the United States must consult with South Korea and seek out a variety of different perspectives, including those of progressives. Once a strategy has been adopted, the United States and South Korea must have in-depth consultations on all of the various aspects of the strategy that may affect the alliance, from how to approach Chinese technology companies to China’s human rights violations against Uighur Muslims to concerns over trade. While tasks such as developing a strategy in consultation with allies should be the very foundation of a strong alliance, they have been largely ignored in recent years, and there is tremendous work to do.

Force posture

U.S. force posture on the Korean Peninsula often can take on outsize importance in perceptions of the alliance. Some policymakers, regardless of their political leanings, believe the U.S. troop presence to be synonymous with the alliance and reductions to be tantamount to signaling an erosion in support for the alliance. This was part of the conversation over the past few years, as Trump repeatedly suggested that reducing U.S. troops on the peninsula was on the table. The way in which Trump made these suggestions—and the way in which he canceled U.S.-South Korea military exercises without consulting Seoul—undermined the alliance.

The key issue that both sides need to keep in mind when it comes to force posture is the alliance has shared goals—and the U.S. military presence and cooperation between the two militaries is just one of the tools that the allies have to achieve these goals. The United States and South Korea must ensure that any force posture discussions—about military exercises, troop levels, or the deployment of weapons systems—happen within the broader context of alliance goals. The number of U.S. troops in South Korea and the schedule of military exercises should not be viewed as sacrosanct, but rather as a way to advance shared interests. For instance, as long as both sides agree that a change in force posture could help advance diplomacy while maintaining deterrence against the DPRK, these changes should be fully considered. Similarly, the United States and South Korea must recognize that issues such as OPCON transfer and SMA negotiations have an impact on the broader alliance, and both sides should work quickly to resolve outstanding questions on both issues.

The U.S.-South Korea alliance is vital to both countries in terms of not only dealing with the threat posed by North Korea but also for its potential to tackle broader regional and global challenges. But for the alliance to be most effective—and to have the widest possible support on both sides—the two countries must strive to better understand one another. This must include efforts from progressives in the United States and South Korea to find common ground on key challenges.

Michael H. Fuchs is a senior fellow at the Center for American Progress. Previously, he was a deputy assistant secretary of state for East Asian and Pacific Affairs. Fuchs has also held positions as special adviser to the secretary of state for strategic dialogues; special assistant to the secretary of state; and deputy national security director for Hillary Clinton’s 2008 presidential campaign.

Haneul Lee is a research assistant for Asia Policy at the Center for American Progress.

The authors would like to thank the Korea Foundation for its generous support, which made this project possible. They would also like to thank the colleagues who took part in the interviews that informed the analysis as well as those who generously provided feedback on this report.