From Covid-19 to the war in Ukraine, recent shifts in the global strategic landscape have presented new challenges for the U.S.-ROK (Republic of Korea) alliance while reinforcing its importance as a foundation for regional peace and stability.
Within this rapidly changing environment, North Korea has found new incentives and opportunities to accelerate its missile testing and nuclear weapons development.
To manage these challenges, the United States and South Korea need to reexamine traditional approaches to North Korea policy and take steps to increase the credibility of U.S. extended deterrence.
The recommendations below, based on a CSIS commission led by President & CEO John Hamre and CSIS Trustee Joseph Nye, present critical, actionable items that will help to ensure that the U.S.-ROK alliance navigates this shifting landscape from a position of strength.
The war in Ukraine has had multiple impacts on the Korean peninsula.
Russia’s invasion of Ukraine has reminded South Korea of the strategic importance of the U.S.-ROK alliance as a buffer against hostility from outside powers. Russia’s nuclear posturing has also intensified South Korea’s concerns about its vulnerability as a nuclear-weapons-free power facing a nuclear-armed North Korea.
For North Korea, the war in Ukraine seems to have further validated its perception that nuclear weapons are critical to its security. Pyongyang has also taken steps that imitate Putin’s tactics in Ukraine, including announcing rationales for the possible preemptive use of nuclear weapons and taking steps to develop tactical nuclear weapons for use on the battlefield.
The war in Ukraine has also facilitated North Korean advances in its nuclear and missile programs insofar as the United States is focused on developments in Europe, and Russia and China are more closely aligned against the United States and are no longer willing to impose sanctions on North Korea following its provocations.
North Korea faces severe internal difficulties stemming from poor health and economic conditions, both of which were made worse by North Korea’s Covid-19 border lockdown since January 2020 and the first known outbreak of the coronavirus in the country in May 2022. These circumstances also incentivize weapons development, as displays of military strength can help to increase support for the regime during difficult times.
Pyongyang was relatively quiet during the first year of the Biden administration, possibly because it was consumed by internal hardships or because it wanted to explore whether the Biden administration might consider lifting sanctions that Pyongyang had aimed to negotiate an end to in the failed 2019 U.S.-North Korea summit in Hanoi.
Since the start of 2022, however, North Korea has conducted weapons tests on more than 37 separate occasions, including its first intercontinental ballistic missile (ICBM) launches since 2017 in March.
CSIS assessed in June 2022 that North Korea had finished all preparations for conducting a seventh nuclear test at the Punggye-ri Nuclear Test Facility.
Continued construction and movement of equipment around the tunnel to the third testing site (South Portal) was observed in satellite imagery captured earlier this year.
Prior to the seventh nuclear test, satellite imagery in October had shown no new developments around Tunnel No. 3 since mid-June, suggesting the site was ready for a nuclear detonation.
North Korea is unlikely to return to diplomacy until it achieves its weapons development goals outlined in recent speeches.
North Korea is unlikely to return to diplomacy until it achieves its weapons development goals outlined in recent speeches. Kim Jong-un articulated these aims in unusual detail in his January 2021 remarks at the Eighth Party Congress of the Workers Party of Korea, in which he mentioned research focused on “perfecting the guidance technology for [a] multi-warhead rocket” and working toward “attaining an advanced capability for making a preemptive and retaliatory nuclear strike by further raising the rate of precision good enough to strike and annihilate any strategic targets within a range of 15,000 kilometres with pinpoint accuracy.” In a more recent statement at a military parade on April 25 this year, Kim reaffirmed his commitment to improving the country’s nuclear capabilities “in terms of both quality and scale.”
North Korea ultimately aims to achieve a reliable capability to penetrate U.S. missile defenses and strike the U.S. homeland. Pyongyang could then use this capability to deter a U.S. attack on North Korea while generating doubts among U.S. allies in the region that Washington would put its own cities at risk by defending its allies from a North Korean attack.
North Korea also aspires to use tactical nuclear weapons as an asymmetric capability to alter the balance of power on the Korean peninsula in its favor, enabling Pyongyang to dictate the terms of interaction with South Korea in the economic, security, and political spheres.
North Korea’s likely ongoing disinterest in engagement as it continues to pursue its weapons development goals should not discourage allied action. With the recent election of Yook Suk Yeol, whose positions on North Korea and regional issues align closely with those of the Biden administration, there is a moment of policy unity between Seoul and Washington that should be used to prepare for whatever actions Pyongyang may take in the coming weeks and months.
The allies should pursue North Korea policies along three tracks: (1) preparing for an eventual return to negotiations, (2) enhancing defense and deterrence capabilities and sanctions enforcement, and (3) communicating support for humanitarian assistance and human rights as separate from denuclearization diplomacy.
Prepare for Diplomacy
Even with low expectations for short-term breakthroughs, the United States and South Korea should continue to signal openness to diplomacy and readiness to talk without preconditions, as the Biden administration has been doing for several months.
Preparing for an eventual return to negotiations should involve devising roadmaps toward complete and verifiable denuclearization that include interim steps to reduce threat levels and build confidence.
The United States should appoint a full-time special representative for North Korea. This individual could work to coordinate potential roadmaps for North Korea’s denuclearization among key stakeholders in Washington, Seoul, and Tokyo.
Enhance Defense, Deterrence, and Sanctions Enforcement
North Korea’s advances in weapons capabilities call for the allies to strengthen their own defense and deterrence capabilities and step up the enforcement of existing sanctions on North Korea.
Key steps to strengthen defense and deterrence include the following:
- Resume U.S.-ROK joint military exercises that were suspended or downgraded in previous negotiations
- Support South Korea’s military improvements, including: (1) the Kill Chain, South Korea’s preemptive strike plan designed to detect an imminent attack from North Korea and destroy its missile launch capabilities before they can be used, (2) early deployment of Iron Dome, (3) directed energy possibilities, including the development of counter-artillery systems that use focused energy instead of physical objects to strike targets, (4) upgraded ship-based defenses, and (5) an additional Terminal High Altitude Area Defense (THAAD) battery – moving South Korea to the top of the list for its purchase.
- Expand space-based cooperation to strengthen reconnaissance capabilities that can detect and deter North Korean threats.
The allies should not consider the re-deployment of U.S. tactical nuclear weapons to the Korean peninsula or the acquisition of nuclear weapons by South Korea under current circumstances.
South Korea and the United States should develop a broad counter-missile strategy to
- detect and defend against North Korean missiles and launchers,
- disrupt its capability networks,
- and destroy its launchers and missiles.
Investigating new concepts of missile defense is also important. This might include boost-phase systems that would help overcome the limitations of current U.S. missile defense systems.
Increasing trilateral defense coordination among the United States, South Korea, and Japan is also increasingly important as North Korea advances its nuclear and missile capabilities. The three countries should reinstate the Trilateral Consultation and Oversight Group as a regular channel of communication and policy coordination on North Korea.
Additional forms of trilateral military cooperation that would bolster deterrence include information sharing, anti-submarine warfare, missile defense, contingency planning, and regular trilateral exercises.
These efforts will enhance defense and deterrence vis-à-vis North Korea while serving as a clear demonstration to North Korea that its actions have consequences.
Increasing trilateral defense coordination among the United States, South Korea, and Japan is also increasingly important as North Korea advances its nuclear and missile capabilities.
Sanctions have also been an important tool to pressure North Korea to denuclearize, but they have been weakened by China and Russia’s lax enforcement. The United States and South Korea, together with Japan, should lead efforts to enforce existing North Korea sanctions.
These efforts could include deterring illegal ship-to-ship transfers and pressuring countries to return North Korean laborers working overseas in violation of international sanctions. The United States, South Korea, and Japan could also expand secondary sanctions against China and Russia if they continue to resist complying with UN Security Council Resolutions.
The United States and its allies should be open to lifting these sanctions to provide a powerful incentive for North Korea, but they should be clear that this would only happen in exchange for substantive and difficult-to-reverse steps on denuclearization by North Korea.
Support Humanitarian Assistance
and Human Rights
Separate from denuclearization diplomacy, the United States and South Korea should consider immediate humanitarian assistance to North Korea through the international aid community to improve conditions for North Korea’s citizens.
Human rights and humanitarian assistance should also remain separate from denuclearization diplomacy. To make progress in this area, the United States must appoint a special envoy for North Korean human rights as soon as possible.
The U.S. extended deterrence commitment to South Korea refers to Washington’s pledge to devote the full range of its military capabilities, including nuclear weapons, to deter and, if necessary, defeat an external attack on South Korea.
For extended deterrence to be effective, North and South Korea must also believe that the United States is willing to use these capabilities to defend its allies—even if it means risking Washington, D.C. or New York to save Seoul or Tokyo.
This involves two central purposes: to deter North Korean aggression in all of its forms, and to prevent nuclear proliferation by providing South Korea with an alternative to developing its own nuclear weapons to meet its security needs. As such, the two allies have sought to avoid policies that put the two purposes of extended deterrence into conflict, for instance, by advancing deterrence but setting back nonproliferation efforts.
The extended deterrence commitment has physical and psychological aspects that both affect its credibility. Acquiring and demonstrating the military capabilities the United States needs to protect South Korea from North Korean threats is critical but insufficient.
For extended deterrence to be effective, North and South Korea must also believe that the United States is willing to use these capabilities to defend its allies—even if it means risking Washington, D.C., or New York to save Seoul or Tokyo. As such, extended deterrence requires consistent U.S. demonstrations and assurances of both capabilities and will.
North Korea’s increasing weapons capabilities, its threats to use nuclear weapons for offensive purposes, and the vulnerability of U.S. national missile defenses to advancing North Korean missile technologies have led South Koreans to question the credibility of U.S. extended deterrence in recent years. This situation calls for the United States to devise ways to enhance the credibility of U.S. extended deterrence in order to reduce South Korea’s (and Japan’s) sense of vulnerability.
Policies to strengthen U.S. extended deterrence should be pursued along six general tracks:
on U.S. Capabilities
The United States should continue to broadcast at the highest levels its commitment to provide extended deterrence to South Korea using “the full range of U.S. defense capabilities, including nuclear, conventional, and missile defense capabilities.”
The United States should also emphasize that the U.S.-ROK “community of fate” forms the core of extended deterrence, regardless of additional U.S. capabilities that may be introduced.
The community of fate refers to the 28,500 U.S. troops in South Korea that tie the country together with the United States strategically, ensuring that North Korea cannot use nuclear weapons or attack South Korea conventionally without killing Americans.
Improve Joint Planning and Execution
There are several steps that could enhance joint planning and execution of various aspects of extended deterrence.
For instance, creating a framework for joint nuclear planning–similar to a NATO planning group for nuclear weapons use, with planning conducted bilaterally and trilaterally (with Japan) and control remaining in the hands of the United States–would help to develop stronger bonds of trust between the allies in the current environment.
Sustaining practices such as sending a senior South Korean liaison officer to U.S. Strategic Command would give South Korea a presence inside the key headquarters that plans for and executes any use of nuclear weapons.
The allies should also reactivate the high-level Extended Deterrence Strategy and Consultation Group (EDSCG).
Expand Trilateral Operations and Dialogue
The United States and South Korea should look for ways to expand trilateral operations and discussions related to extended deterrence.
For instance, the United States could supplement the two extended deterrence dialogues with South Korea and Japan with a track 1.5 trilateral strategic exchange in order to stay informed about developments in each country and identify opportunities for coordination.
The allies could also consider undertaking a nuclear planning exercise trilaterally.
The United States should streamline protocols for direct Space-Based Infrared System (SBIRS) access to South Korea in addition to the geographic commanders, as the United States does for Israel and Japan.
Adjust and Improve U.S. Military Capabilities
The United States should consider changing its regional strategic and nuclear posture to allow for more robust and constant demonstrations of U.S. capabilities. This could involve the continuous presence in the region of either U.S. submarines equipped with nuclear cruise missiles or strategic bombers or investing in infrastructure in South Korea to receive U.S. dual-capable aircraft.
The United States should improve its national missile defense capabilities vis-à-vis North Korea, including through accelerating plans to deploy 20 additional interceptors equipped with Next Generation Interceptor technology, currently slated for 2028, and investing in boost-phase missile defense technologies. The United States should also restore funds for and continue pursuing its nuclear sea-launched cruise missile program.
Prepare for the Possible Future Redeployment of U.S. Low-Yield Nuclear Weapons
The United States should lay pre-decisional groundwork to prepare for the possible redeployment of low-yield, or tactical, nuclear weapons to South Korea at some point in the future.
The United States could consider tabletop planning exercises with South Korea that would be explicitly pre-decisional and leave the timeline and scope of weapons deliberately ambiguous. Decisionmaking would be calibrated to shifts in the security environment and the North Korean threat level.
The redeployment of tactical nuclear weapons could heighten tensions on the peninsula despite its intended deterrent effect. This type of early groundwork would signal commitment to the allies and resolve to North Korea while not yet crossing the proliferation threshold. It would also create new pressure on North Korea to stop ratcheting up threat levels if it does not want to see tactical nuclear weapons return to the peninsula.
Align Positions on China
The United States and South Korea should coordinate positions on China. This could involve establishing a mechanism to bilaterally share assessments of the implications of China’s evolving military capabilities for the Korean peninsula and coordinating potential responses.
The allies should also develop plans to jointly respond if Beijing again uses pressure tactics aiming to derail allied deterrence initiatives directed toward North Korea, as it did when it used economic retaliation to punish South Korea for its deployment of a U.S. THAAD battery in 2017.
These steps should help to increase trust and belief in U.S. extended deterrence among South Koreans, even as North Korea continues to build its weapons capabilities.
These steps should help to increase trust and belief in U.S. extended deterrence among South Koreans, even as North Korea continues to build its weapons capabilities.
Currently, North Korea’s nuclear weapons and ballistic missile programs look unstoppable. Decades of failed denuclearization diplomacy, however, cannot deter the allies from seeking new avenues of engagement with the modest goal of slowing down the program’s growth.
Failing that objective, the United States must be cognizant that contingency planning, enhanced military readiness, and strengthened extended deterrence measures with South Korea and Japan serve to make U.S. alliances in Asia stronger, which in turn will impose costs on North Korea for its proliferation behavior.
- Commission Co-Chairs: President & CEO John Hamre and CSIS Trustee Joseph S. Nye Jr.
- Director: Dr. Victor Cha, Senior Vice President for Asia and Korea Chair
- Associate Director: Dr. Katrin Fraser Katz, Adjunct Fellow (Non-resident), Korea Chair
- Special thanks to Andy Lim, Associate Fellow, Korea Chair, and Ellen Kim, Deputy Director and Senior Fellow, Korea Chair
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The New Landscape:
- Russian President Vladimir Putin greets North Korean Leader Kim Jon-un on his first visit to Russia in April 2019. | Mikhail Svetlov via Getty
- Kim Jong-un speaks with military officials following the test of new-type tactical guided weapon in North Korea, on April 17, 2022. | AFP PHOTO/KCNA VIA KNS
- Health officials disinfect a room in a Pyongyang hospital on April 1, 2020. | Kim Won Jin via AFP/Getty
North Korea's Actions and Objectives: A television screen shows a news broadcast with file footage of a North Korean missile test, at a railway station in Seoul on September 29, 2022. | JUNG YEON-JE/AFP via Getty Images
Policy Recommendations on North Korea:
- Kim Jong Un appears in a face mask on television for the first time to order nationwide lockdowns following the first confirmed cases of COVID-19 in North Korea on May 12, 2022. | Anthony Wallace via AFP/Getty
- U.S. President Joe Biden and ROK President Yoon Suk Yeol attend a press conference during their first summit in Seoul on May 21, 2022. | Getty Pool
- Components of the South Korea's first THAAD system arrive on the peninsula in March 2017. | Master Sgt. Jeremy Larlee via DVIDS
- The USS Ronald Reagan (center) and South Korean and Japanese naval ships sail in formation in waters east of the Korean Peninsula on September 30, 2022. | U.S. Navy photo by Mass Communication Specialist 3rd Class Gray Gibson
- North Korean children eat lunch at a government run kindergarten on July 18, 2005. | Gerald Bourke/World Food Programme via Getty
Policy Recommendations on U.S. Extended Deterrence:
- A B-2 Spirit flies into position during a refueling mission over the North Atlantic Ocean on June 11, 2014. | U.S. Air Force photo by Tech. Sgt. Paul Villanueva II
- The USS Ronald Reagan participates in naval exercises with South Korea and Japan in waters east of the Korean Peninsula on September 29, 2022. | U.S. Navy photo by Mass Communication Specialist Seaman Natasha Chevalier Losada
- South Korean and U.S. soldiers take part in a joint military exercise at the Rodriguez Live Fire Complex on August 31, 2022 in Pocheon, South Korea. | South Korean Defense Ministry via Getty Images
- The USS Ronald Reagan and a U.S. Navy Los Angeles-class fast-attack submarine sail near the Korean Peninsula during naval exercises on September 30, 2022. | U.S. Navy photo by Mass Communication Specialist 3rd Class Gray Gibson
- A ground-to-ground missile is fired during a U.S. and South Korea joint training exercise on May 25, 2022 in East Coast, South Korea. | South Korean Defense Ministry via Getty
- South Korean Air Force F-15Ks and U.S. Air Force F-16 fighter jets fly over the Korean Peninsula in response to North Korea's IRBM launch on October 4, 2022. | South Korean Defense Ministry via Getty
- Chinese President Xi Jinping speaks during the meeting of the standing committee of the Political Bureau of the 20th CPC Central Committee at The Great Hall of People in Beijing on October 23, 2022. | Lintao Zhang/Getty Images