What to Expect From Yoon Suk-yeol’s Policy on North Korea

The election of Yoon Suk-yeol, the candidate of the conservative People Power Party, in South Korea’s presidential election on March 9 was an explicit signal for countries involved in regional issues in East Asia that Seoul’s policy will shift. Under Yoon, South Korea is expected to move further toward the U.S. side while defining North Korea as a major adversary. Yoon pledged during his campaign that his administration will strengthen the South Korea-U.S. military alliance by invigorating joint military drills and deploying additional THAAD (Terminal High Altitude Area Defense) anti-missile launchers.

The state actor that will be most affected by dramatic changes in Seoul’s stance will be North Korea.

One of the security hot potatoes during the campaign was Yoon’s remarks over a possible preemptive strike against the North. At his New Year’s press conference, Yoon raised the possibility of launching a preemptive strike using the Kill Chain in the “three-axis” defense system if there are signs of North Korea launching missiles toward the South. Conservative hawks around Yoon have also repeatedly raised the necessity of reviving this “three-axis” system in order to show strength toward the North.

The three-axis defense system refers to South Korea’s military response to North Korea’s missile attacks. The three-axis system is also referred to as the “three Ks,” referring to the main programs involved: Kill Chain (the first component, referring to a pre-emptive strike on North Korea’s nuclear and missile sites), Korean Missile Defense System (the second component, meant to intercept North Korea’s missiles), and Korea Massive Punishment and Retaliation (the third component, referring to mass retaliation against North Korea following an attack on the South).

This three-axis defense system was completed during two consecutive terms of conservative presidents from 2008 to 2017. However, current South Korean President Moon Jae-in’s Defense Ministry replaced this term with a system for responding to threats from nuclear weapons and weapons of mass destruction (WMD) in January 2019. This decision was viewed as a follow-up measure to encourage substantive progress in denuclearization of the Korean Peninsula after Moon held several inter-Korean summit meetings with North Korean leader Kim Jong Un.

In a press conference introducing his foreign policy, Yoon made clear that South Korea should be a key actor, not a mediator, in the denuclearization of North Korea. While announcing his initiative to install a trilateral South Korea-U.S.-North Korea liaison office at the demilitarized Panmunjom area, he also pledged to provide humanitarian support to North Koreans, which has been the main policy of progressive governments on North Korea, regardless of political or denuclearization circumstances in the Korean Peninsula. Yoon also said he will expand cultural exchanges and communication between the two Koreas based on the principle of reciprocity.

Consequentially, the things that Yoon highlighted in the press conference as his key policies on North Korea seem progressive – steps like humanitarian aid can actually improve ties with North Korea. However, such initiatives are unlikely to take place in practice. They will require buy-in from Pyongyang, which is unlikely based on Yoon’s aggressive policies to deter North Korea’s nuclear weapons and missile threats.

Deterring North Korea: THAAD and Tactical Weapons

While Moon approached North Korea issues as a peacemaker pursuing dialogue first, Yoon will likely pursue an aggressive deterrence posture by building up advanced missile programs to deter North Korea’s military provocations. Yoon has emphasized the importance of posing a strong deterrence against North Korea and also pledged to develop a comprehensive military alliance with the United States and extended deterrence on North Korea’s nuclear weapons.

One of the actions Yoon could take to follow the South Korean conservative governments’ old school policy for developing ties with the U.S. and confronting North Korea is deploying more THAAD batteries.

Yoon has repeatedly expressed the necessity of additional THAAD deployments to protect the country from North Korea’s ballistic missiles, although he has not mentioned specific locations for the new batteries. The incoming Yoon government will closely work with the U.S. President Joe Biden’s administration to deploy additional THAAD batteries on the South’s soil after Yoon takes office in May.

THAAD is a controversial issue in South Korea. Some experts have said that THAAD cannot intercept North Korea’s short-range ballistic missiles (SRBM) targeting Seoul, the capital of South Korea, or the greater Seoul area, as short-range missiles would fly at a low altitude. Also, former USFK Commander General Vincent K. Brooks remarked that Seoul doesn’t need to deploy additional THAAD batteries if it operates THAAD together with other anti-missile systems South Korea has built.

South Korea has been working on developing a homegrown “Iron Dome”-style anti-missile program. Lee Jae-myung, the presidential candidate of the ruling Democratic Party, who lost the election by just 0.7 points, criticized Yoon’s emphasis on the U.S.-made THAAD system, saying it will harm South Korea’s defense industry. South Korea successfully tested its L-SAM (long-range surface-to-air missile) interceptor this year, and expects to have it ready to deploy in 2026. Lee argued that there is no reason to deploy THAAD if the country can deploy L-SAM as planned.

THAAD deployment will also carry a heavy cost. China viewed the missile defense batteries as a threat to its own security interests and hit South Korea with painful economic countermeasures after Seoul’s decision to deploy THAAD in 2016. Most of the critics over Yoon’s decision fear the possibility of facing China’s economic retaliation again if he carries through on his plan to expand THAAD deployments. Yoon has not provided any details on how to prevent China from imposing sanctions again.

However, Yoon has never compromised on his plan to deploy more THAAD batteries, implying his fundamental approach to North Korea issues will be to respond with “strength to strength,” to borrow a phrase from North Korea.

Additionally, his administration will likely seek room to redeploy tactical weapons. Park Jin, who has been nominated as Yoon’s foreign minister, expressed the incoming administration’s interest in taking steps for extended deterrence against the North’s missile threats during a meeting with White House National Security Advisor Jake Sullivan a week ago.

Since the failed Hanoi summit between then-U.S. President Donald Trump and North Korean leader Kim Jong Un in 2019, North Korea has consistently demanded the U.S. and South Korea remove “hostile policies,” which refer to the U.S.-led economic sanctions, South Korea-U.S. joint military exercises, and the roughly 28,500 U.S. troops stationed in South Korea to restore the stalled nuclear talks.

However, Yoon has pledged to reinvigorate the currently scaled-backed joint military exercises and pursue CVID (Complete Verifiable Irreversible Denuclearization) of the Korean Peninsula, which is unacceptable for North Korea. That approach is highly likely to trigger Pyongyang to escalate tensions on the Korean Peninsula by conducting a nuclear test or testing its new ICBM system, perhaps disguised as a space launch, in the coming months.

North Korea’s most important holiday, the 110th birth anniversary of Kim Il Sung, the founder of North Korea and late grandfather of Kim Jong Un, passed relatively quietly, with mostly civilian activities aside from a short-range missile launch on April 16. But on April 25, the 90th anniversary of the founding of the Korean People’s Revolutionary Army, Pyongyang hosted a military parade that showcased its missile technology. Speaking at the parade, Kim heavily emphasized the importance of North Korea’s nuclear program to national “self-defense.” That raises the possibility of Pyongyang conducting a nuclear test in the future,. North Korea has already been accused of restoring the Punggye-ri nuclear testing site and reactivating the Yongbyun nuclear complex.

Meanwhile, South Korea and the U.S. launched their joint military drills on April 18. Washington and Seoul had scaled back their joint drills as part of a friendly gesture to Kim in the hopes of making substantive progress during nuclear talks with North Korea in 2018 and 2019. However, as the U.S. and North Korea failed to reach an agreement, South Korea-U.S. joint military drills will likely take place at similar levels to the drills conducted before Moon took office. North Korea has strongly denounced South Korea-U.S. military exercises as significant threats to its security, utilizing the drills as a pretext for its own nuclear and missile developments.

South Korea and the Quad

Another main initiative of Yoon for strengthening ties with the U.S. is joining the Quadrilateral Security Dialogue (Quad) to boost security cooperation with other U.S. allies.

Yoon has sought ways to build more ties with the U.S. by calling Moon’s policies pro-China. As Beijing views the U.S.-led working groups in the region, such as the Quad, as anti-China coalitions that seek to weaken Beijing’s leverage in East Asia and the larger Indo-Pacific region, the Moon government has hesitated to firmly participate in such groups.

Critics of Yoon’s harder approach have expressed concerns over the possibility of friction with China, which remains South Korea’s most important trade partner. Yoon’s key initiatives – expanding THAAD and joining the Quad – may cause Beijing to impose strong economic retaliation.

There will be an obstacle within the Quad itself, which consists of Australia, India, Japan, and the United States. Despite Yoon’s eagerness to join the Quad, Japan would not welcome South Korea to be part of the group, as Tokyo would wish to remain the top key partner of the U.S. in East Asia. Japan has adopted a similarly unwelcoming attitude toward occasional suggestions for South Korea to join the G-7 as a permanent member.

Washington has not publicly welcomed Yoon’s plan to join the Quad, saying the four-state group has no plan to cooperate with other state actors at this time. However, as the incoming South Korean president has explicitly shown his clear desire to join, Washington will have to decide whether to persuade other Quad members, especially Japan, to firmly induct South Korea into the Quad or entice other nations, such as New Zealand and Vietnam, to join the group with South Korea to make it into “Quad Plus.”

Should Seoul join the Quad or a similar grouping, North Korea will seize that moment as a strong motivation to push for achieving Kim’s five-year military modernization plan, with the apparent support of China. Given that both Yoon and Kim are dedicated to a “strength to strength” approach, we can expect that the two Koreas will keep building up more missiles, intensifying the arms race on the Korean Peninsula. Consequentially, in the next five years, the diplomatic overtures of Washington and Seoul toward Pyongyang will largely be hollow, as pursuing more advanced armaments to deter North Korea’s military provocations and missile threats will be the only option that remains on their tables.

In the end, Koreans will question whether a peace process to make a nuclear-free Korean Peninsula through dialogue is possible or simply an idealist’s dream. In the wake of the Ukraine crisis, more and more Koreans will likely demand that Seoul develop its own nuclear weapons or deploy tactical nuclear weapons to firmly protect the country from North Korea’s nuclear and missile attacks – which ultimately would make the Korean Peninsula a classical battleground of the new Cold War.