December 12, 2019

U.S.-South Korea Tensions: What’s at Stake?

U.S. Defense Secretary Mark Esper (L) meets with South Korean Defense Minister Jeong Kyeong-doo in Seoul on November 15, 2019. Chung Sung-jun/Pool/AFP/Getty Images

Washington’s request that Seoul pay more for their military alliance has heightened tensions between longtime allies and poses risks for regional security.

By Scott A. Snyder
Senior Fellow for Korea Studies
Director, Program on U.S.-Korea Policy
Council on Foreign Relations

In a rare public rift between the United States and South Korea, negotiations between the two allies over how much each side should pay for their military alliance recently fell apart. The rising tensions could affect North Korean nuclear negotiations, policy toward China, and trust in the U.S.-led alliance structure in the Asia-Pacific region.

How far apart are the two countries in their negotiations?

The gap between the two countries is significant. U.S. President Donald J. Trump reportedly requested that South Korea spend $4.7 billion per year to support U.S. operations in the country. This year, South Korea paid around $924 million as part of a one-year agreement on burden sharing that replaced the previous five-year agreement, known as the Special Measures Agreement. Negotiations between the two sides to replace their existing agreement, which expires at the end of the year, broke down in November.

The difference is largely due to the U.S. request that South Korea start paying for new categories of costs. South Korea is currently responsible for covering 40–45 percent of nonpersonnel costs on the Korean Peninsula, including local salaries, logistics, and construction projects. It also spends billions of dollars on military equipment purchased from the United States. The Trump administration is now asking Seoul to cover U.S. costs for operations, equipment, and exercises outside of South Korea but related to defense of the peninsula.

But the South Korean government has thus far rejected the new expenditures and will likely continue to resist. A reasonable, double-digit percentage increase in costs might be possible, but South Korean taxpayers are highly unlikely to accept responsibility for covering costs in support of U.S. forces and operations not located in South Korea.

How does this rift affect North Korean nuclear negotiations?

The presence of more than twenty-eight thousand U.S. military personnel on the Korean Peninsula has served as a deterrent against North Korean aggression ever since the U.S. defense commitment to South Korea went into force in 1954. 

However, there have been mounting concerns in the U.S. Congress that Trump could either prematurely remove U.S. forces from the Korean Peninsula as part of a bad deal with North Korean leader Kim Jong-un or demand force reductions to punish South Korea for what he perceives as free riding. In light of these concerns, Congress clarified its ability to limit U.S. force withdrawals from the Korean Peninsula as part of the 2019 Defense Authorization Act. The act bars the reduction of U.S. forces on the peninsula to below twenty-two thousand. 

The removal of U.S. forces from South Korea is a long-standing goal of North Korea, but it would carry both opportunities and risks for Pyongyang. On one hand, South Korea would be more vulnerable to extortion and nuclear blackmail without protection from the United States. On the other hand, South Korea’s conventional technological superiority over the North would no longer face restraints imposed by a United States concerned about entrapment in a new Korean conflict.

What does this mean for Japan?

Japan faces similar exorbitant demands from the Trump administration on military burden sharing and has been closely watching U.S.-South Korean negotiations. Ironically, the Trump administration’s demands should help drive these two U.S. allies together, but that hasn’t happened given recent tensions between them.

What does China stand to gain?

As China’s regional influence and military capabilities continue to grow, Beijing could perceive the U.S.-South Korea relationship as a weak link in the Asia-Pacific alliance architecture in which the United States has been the dominant player for decades.

In recent months, China has prioritized restoring its relationship with South Korea, revealing how it could try to capitalize on current frictions as part of a strategy to displace the United States as the dominant player in Asia. China wants to ensure that the raison d’être of the U.S.-South Korea alliance remains centered on North Korea and not on impeding Chinese interests in the region.

Seoul has also sought to improve military ties with Beijing by establishing hotlines and other exchanges. But China’s economic retaliation over South Korea’s decision to host a U.S. missile defense system has remained an obstacle.

Originally published by the Council on Foreign Relations, 11.26.2019, under the terms a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International license.