Denuclearization is at the top of the negotiating agenda with North Korea, but reducing the size and capabilities of its conventional defense establishment should be a high priority for the US and South Korea as well. Success in accomplishing this goal will help normalize relations with the North, which will not only help build a new peace and security regime for the Korean Peninsula, but also improve prospects for denuclearization. The core of such a demilitarization program should consist of reductions in North Korea’s conventional military capabilities, confidence building measures to reduce the risk of surprise attack or an inadvertent conflict, multilateral cooperative threat reduction programs, and assistance for defense conversion and military demobilization. Changes in the US military posture in South Korea—if implemented in a prudent manner—are compatible with this initiative and could even contribute toward its success.

(This first appeared in 38 North here.)

Introduction

In the long-game now being played by the US, South Korea and North Korea to usher in peace and security on the Korean Peninsula, it is likely that changes will eventually be made to US troop levels in the South if, as stated in the June 12 Singapore Summit declaration, the US and North Korea establish “new” relations and create a “lasting and stable peace regime” on the peninsula. But there is a right way and a wrong way to make these changes. Thus far, President Trump, like former President Jimmy Carter in 1977, is considering the wrong way: unilateral reductions driven by budget considerations or misplaced pique over South Korean burden sharing, divorced from the broader movement toward a future security regime for Korea. Instead, the future of US forces in South Korea should be determined by two factors: first, the geo-strategic importance of the Korean Peninsula and the need to maintain a balance of power in Northeast Asia to protect vital US national security interests; and second, reductions in North Korea’s conventional military threat, especially its capacity to launch a massive attack with little or no warning.

North Korea has a potentially critical role to play in implementing risk reduction measures for the Korean Peninsula and at the appropriate time, both the Washington and Seoul will need to engage Pyongyang on this issue. But first, the US and South Korea should jointly develop a road map for the demilitarization of North Korea including reductions in Pyongyang’s conventional military capabilities; confidence building measures (CBMs) to reduce the risk of surprise attack or an inadvertent conflict; multilateral cooperative threat reduction (CTR) programs to help dismantle North Korean conventional weapons and equipment; and defense conversion and military demobilization assistance to the North to free up resources for economic development.

In the context of these programmatic initiatives, conventional defense improvements in US and ROK forces, an end to the armed stand-off with North Korea, the maintenance of a strong US-ROK alliance, and the configuration of US forces on the peninsula could be changed without undermining deterrence and stability and the balance of power in Northeast Asia. Over time, in response to these changing dynamics, the US-ROK alliance might evolve into a different defense relationship that could lead not only to changes in US troop levels, but also greater flexibility on the types of forces it maintains in the region.

Dodging a Bullet—for Now

If the efforts to “build a lasting and stable peace regime on the Korean Peninsula” come to fruition, as set out in the summit declaration, it could put additional pressure on the US to reduce or withdraw its troops, unless US officials are successful in persuading Seoul that vital national security interests in Northeast Asia require a continued US military presence to contain the long-term Chinese threat to the region. Some recent public opinion polling suggests that the South Korean public would support a continued US military presence as a counterweight to China, even if the North and South sign a peace treaty and normalize relations.

It is commonplace to believe that Kim Jong Un wants US forces to leave South Korea and an end to the US-ROK alliance. It is far from clear, however, that this is the case. From 1992-2011 and the death of Kim Jong Il, the North did not want to see US troops leave the peninsula. North Korean logic has always been that US troops in the South are a problem as long as they are pointed at North Korea, but if bilateral relations become normal and Pyongyang no longer sees the US as an enemy, the troops would no longer be a problem.

It is uncertain whether Kim Jong Un shares his father’s view. But it is not out of the question, since one of the primary purposes for his move toward the US is to give the North some safety from China. From Kim’s perspective, American troops on the peninsula provide a counterweight to Chinese influence. Thus, if the US and North Korea normalize their relationship, Pyongyang may have little interest in reducing or removing American forces from the South. Moreover, the South Korean public is going to expect and demand—and the government will program for—its own force reductions as the situation with North Korea becomes less tense, which could create incentives for the US to maintain its military presence at current levels to compensate for reduced ROK forces.

All this said, there is nothing inherently wrong with making adjustments to US forces in South Korea based on the evolution of the North Korean threat, changes in military technology, opportunities to rationalize and streamline command and control arrangements, improvements in South Korean military conventional capabilities, or the need to meet other competing demands (as the Bush administration did in 2004 when it re-deployed 10,000 troops from South Korea to Iraq during the second Gulf War). Changes in the US military presence in Europe and Japan have been made over the years in response to such factors. Nor is there anything sacrosanct about the number 28,500—an arbitrary figure arrived at without any systematic assessment of operational requirements that took on a life of its own.

The actual defense of South Korea does not depend on these forces, but rather on the capacity to rapidly reinforce the South with additional ground troops, air and naval forces from the US and elsewhere in the region. It is doubtful that North Korea would be any less deterred if the US made modest reductions in its troop presence as long as enough capability remained in place to protect and support those reinforcements.

The Penny Wise and Pound Foolish President

Trump seemingly wants to withdraw all US forces from Korea because of the costs, without considering the long-term consequences for America’s credibility and influence in the Asia-Pacific region and its global alliance network that helps to maintain the peace. In the president’s mind, South Korea is an ungrateful ally that can afford to defend the country without American protection and cheats America on trade. As he sees it, removing our troops would strike another blow for his “America First” doctrine. But his math is all wrong and so his strategic thinking.

First, the US troop presence in South Korea is a bargain. The South Koreans pick up 50 percent of the tab for maintaining those troops and have often helped defray the substantial costs the US has incurred over the years for modernizing and upgrading its military facilities in the country—such as when Seoul agreed to pick up part of the tab for hosting deployments of the American THAAD missile defense system. The residual costs borne by the US for those troops is a rounding error in the Pentagon’s budget and inconsequential for the federal budget or the country’s $18 trillion GDP.

Second, the US would have to bear 100 percent of the cost of bringing these troops back home and relocating them to facilities across the United States. This would likely please members of Congress who have facilities in their districts and it will mean more jobs for American workers. But the only way to reap substantial savings would be to deactivate these forces and their associated equipment and assets—a decision that makes no sense if the US intends to maintain its security commitment to South Korea.

Finally, the US alliance with South Korea embodies more than just a defense commitment to that country; it is also a pillar of the US position in the Asia-Pacific region and central to preserving a favorable balance of power with China. The US forces based there are critical to the defense of Japan and could be used to project US military force more broadly in the region if circumstances warranted. A rapid and unilateral pullout would further damage whatever is left of the credibility of US security commitments in the region.

Risk Reduction and Conflict Prevention

The combination of the Trump-Kim Summit in Singapore and the Moon-Kim Summit in Panmunjom have launched a process to negotiate a peace treaty that will inevitably involve the other powers with stakes in the security and stability of the Korean Peninsula. It is hard to imagine the construction of a durable peace and security regime that ignores the North’s conventional military threat to combined US and ROK forces; this includes not only the thousands of artillery pieces, rockets and missiles that are poised to attack Seoul from just outside the demilitarized zone but also the infiltration of North Korean special operations forces deep into South Korean territory to disrupt both the organization of US-ROK military operations and the flow of US reinforcements. The absence of transparency on peacetime North Korean troop movements and military activities also heightens the risk of a miscalculation that could trigger a conflict.