Table of Contents


Chung Min Lee

The most striking feature of the security environment on the Korean Peninsula is the gap between assessments made by political leaders and the growing array of asymmetrical threats emanating from North Korea. The “Korea Net Assessment 2020” was prepared to provide nongovernmental analysis on the current and evolving military situation on the Korean Peninsula. Various official assessments such as South Korea’s defense white papers and numerous reports published by the U.S. Department of Defense provide critical overviews of the evolving military balance between the two Koreas. It is hoped that this study will be seen as a more nuanced assessment of significant military developments on the peninsula.

All of the study’s contributors based their findings and analysis solely on their individual and personal capacities, and these findings do not represent directly or indirectly the positions or views of the institutions and organizations they belong to. Moreover, this study was based entirely on publicly available sources. It is hoped that the “Korea Net Assessment 2020” will complement existing studies on the military situation on the Korean Peninsula.

Chung Min Lee
Chung Min Lee is a senior fellow in Carnegie’s Asia Program. He is an expert on Korean and Northeast Asian security, defense, intelligence, and crisis management.
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Understanding the confluence of forces on the Korean Peninsula is arguably more difficult now than at any other time since the end of the Cold War. Republic of Korea (ROK) President Moon Jae-in continues to believe that North Korean Supreme Leader Kim Jong Un is sincere about denuclearization, while U.S. President Donald Trump argues that U.S.-ROK combined exercises are far too expensive and are threatening to North Korea. Never has an occupant of the White House enacted such an erratic North Korea policy, especially while decrying one of the United States’ most trusted allies—South Korea—as a defense free rider. In fact, the ROK remains a valuable U.S. ally who pays far more toward shared defense costs than the Trump administration gives it credit for.

Trump’s new approach to North Korea policy has had an extremely mixed impact. In some respects, Seoul has inwardly welcomed his personalized diplomacy—as evidenced by his unilateral cancelation of military exercises, which caught even the Pentagon off guard—because the South Korean government is keen on providing Kim with political incentives to denuclearize. Trump’s denigration of alliance cohesion and his constant demands that major allies like Germany, Japan, and South Korea dole out billions of dollars toward shared defense costs have already had consequences.

If Trump wins a second term in November 2020 and if ongoing negotiations between the United States and South Korea do not quite meet his requirements for cost sharing, it is not totally impossible to imagine that Trump would seriously consider a partial and symbolic withdrawal of U.S. forces from the peninsula. To be sure, the U.S. secretary of defense would have to certify any significant withdrawal of U.S. forces, and the Congress will also have a say. But if Trump feels strongly that South Korea has not paid its fair share of common defense costs, and if he thinks he needs to provide an additional political incentive for Kim to reach a nuclear agreement, the U.S. president may seriously contemplate downsizing the U.S. forces on the peninsula.

For his part, Moon continues to believe that a peace regime can be built if the United States reaches a major nuclear deal with North Korea, agrees to officially end the Korean War by signing a peace treaty, and establishes a series of structures and mechanisms designed to terminate the last vestiges of the Cold War on the Korean Peninsula. His administration asserts that its attempt at rapprochement with North Korea is premised on a strong defense posture. And the South Korean defense budget has increased significantly. For example, this increase is enabling the ROK Air Force to order additional F-35s as part of efforts to modernize its combat aircraft. This is a positive development, but heavy defense investments are also driven by South Korea’s rapidly declining birthrate and negative demographic outlook as well as the government’s desire to revert wartime operational control (OPCON) as soon as conditions permit.

There is a significant gap between Trump’s and Moon’s rosy appraisals of the chances of a nuclear deal and lasting peace and the unchanged security landscape on the peninsula. By all indications, the military situation on the Korean Peninsula has not improved since the advent of the Trump and Moon administrations. Contrary to Trump’s statement soon after the June 2018 Singapore summit that North Korea’s nuclear weapons no longer pose a threat, the exact opposite is true: North Korea’s nuclear arsenal has continued to grow on Trump’s and Moon’s watch.1 And the Korean People’s Army (KPA) has not stopped amassing ballistic missiles, including submarine-launched ballistic missiles (SLBMs). Moreover, the KPA’s order of battle, exercise regimes, modernization of conventional forces, and political-military directives have remained unchanged. Indeed, even with the conclusion of the September 2018 military agreement on confidence-building measures (CBMs) between the two Koreas, the KPA has not shifted its military posture or deployments.

The novel but capricious U.S. policy toward North Korea, Trump’s highly personalized negotiating strategy coupled with his limited understanding of the relevant geopolitical and security issues, Moon’s insistence on sustaining his push for inter-Korean peace, Kim’s simultaneous efforts to modernize his nuclear weapons and other asymmetrical assets, and China’s growing cooperation with North Korea all have resulted in a fundamental dichotomy: while political leaders in Seoul and Washington maintain that peace is around the corner, the strategic realities on the ground indicate otherwise.

At least five major issues have received the lion’s share of attention in ROK-U.S. relations since 2017, when both Trump and Moon took office. These issues include how the allies should: (1) cope with North Korea’s increasingly advanced nuclear arsenal and array of ballistic missiles including SLBMs; (2) compensate for the degradation of South Korea’s independent military capabilities and combined ROK-U.S. combat capabilities in the aftermath of canceled, postponed, or significantly reduced combined exercises and training; (3) deal with Trump’s unprecedented demand that South Korea pay far more in shared defense costs and the various negative ramifications of that demand, including the weakening of political support in South Korea for the alliance; (4) effectuating conditions-based reversion of wartime OPCON from the United States to South Korea at the earliest possible moment; and (5) the impact of the Moon administration’s Defense Reform 2.0 on interoperability. These issues are examined in-depth by the assessment’s contributors.

As noted above, all of the contributors to this volume provided their own independent and personal views on key aspects of the military situation on the peninsula. The overriding insight of this study is how little has changed militarily in North Korea since the advent of new administrations in Seoul and Washington in 2017. There are inherent limitations to using open sources, such as the inability to track official discussions and negotiations and ongoing bilateral and multilateral security and defense coordination. Yet, at the same time, significant freedom flows from using open sources and not being necessarily constrained by official perspectives and standard operating procedures. Many of the contributors have had direct government experience that has enriched their understanding of critical security and military issues.

In chapter one, Chung Min Lee outlines how political calculations have repeatedly led Moon and Trump to downplay the risks of North Korea’s nuclear weapons program despite the lack of any credible evidence that Kim is taking serious steps to dismantle his arsenal. In chapter two, Kim Min-seok evaluates the changing military balance between the two Koreas’ respective conventional forces, noting how Pyongyang’s quantitative advantage is matched by Seoul’s growing qualitative edge. In chapter three, Shin Beomchul offers a view from South Korea on how the military readiness of the ROK-U.S. alliance is being affected by CBMs with North Korea and cost-sharing negotiations between Washington and Seoul.

Next, Bryan Port examines the strategic versus operational readiness of combined U.S.-ROK forces. In chapter five, Jina Kim analyzes how South Korea is contending with neighboring China’s more assertive military posture and power projection capabilities. In the final chapter, Kathryn Botto delineates what hurdles South Korea and Japan must overcome to rely less on the United States as an intermediary when it comes to bolstering trilateral security cooperation in Northeast Asia.

Between North Korea’s still advancing capabilities and China’s growing clout in Northeast Asia, the allies must navigate a host of threats that are becoming more lethal and complex. Of the many outstanding military challenges in the world today, the accelerated tempo at which North Korea’s weapons of mass destruction programs are advancing and the still formidable nature of its conventional forces stand out as some of the most dangerous. Despite unprecedented political changes in Seoul and Washington since 2017, the steady pace at which North Korea’s nuclear weapons and ballistic missiles programs continue to advance is a sobering reality. This does not mean that the ROK military has stood still. It is amid a concerted military modernization program of its own that will pay key dividends by the late 2020s. And despite the unparalleled disruptions created by Trump, the U.S.-ROK military alliance remains, for the time being, on solid ground. Indeed, those in alliance management institutions on both sides of the Pacific Ocean have never worked as hard to keep the alliance on an even keel.

Nonetheless, it is also undeniable that the penchant for engagement and the desire not to anger North Korea despite Pyongyang’s calculated provocations and probes have never been more pronounced in South Korea. Such political stances have affected the ROK’s military readiness to the extent that the Ministry of National Defense, for example, has to tread very carefully when assessing the full range of North Korean threats. If the ministry or the ROK armed services continue to see North Korea through politically acceptable prisms, there is little doubt that objective intelligence assessments on all key dimensions of the North Korean threat will falter. The consequences of intelligence failure in a country such as South Korea are immense. And while the search for and the making of lasting peace between the two Koreas is necessary, such efforts can never come at the cost of the ROK’s core national security interests.

All military environments are dynamic and subject to various political forces. But given the enormous stakes on the Korean Peninsula, it is absolutely essential for security experts, intelligence officers, members of the defense community, and, most of all, critical policymakers to have access to depoliticized net assessments. In democracies, armed forces must follow directives from their respective political superiors. However, it is equally critical for the countries’ political leaders to base their decisions on unbiased intelligence and provide their militaries, to the greatest extent possible, with depoliticized security choices. The struggle for ensuring a free, democratic, and a prosperous ROK with requisite defense capabilities and strategies is an ongoing mission that is shared with its most important ally, the United States.

This project was made possible with support from the Korea Foundation.


1 Donald J. Trump, @realDonaldTrump, Twitter post, June 13, 2018, 3:56 PM,