South Korea’s two leading presidential candidates clashed over plans to reinforce national missile defense against North Korea, while showing discrepancy in their approach to US and China in a two-hour TV debate aired Thursday.

The four presidential candidates’ first public discussion on foreign and security policy conspicuously centered on ways to enhance missile defense, which has been challenged by North Korea’s rapidly advancing missile and nuclear capabilities.

North Korea fired nine ballistic missiles and two land-attack cruise missiles (LACM) in seven discrete launches from Jan. 5 to 30.

Recently launched missiles, including a KN-23, KN-24, and Maneuverable Reentry Vehicle (MaRV), have notably enhanced survivability and maneuverability. Analysts view that the newly developed missiles are capable of penetrating and incapacitating the missile defenses of South Korea, the US, and their allies.

But People Power Party presidential candidate Yoon Suk-yeol and presidential nominee Lee Jae-myung of the ruling Democratic Party of Korea diverged in ways to build and upgrade missile defense against North Korea’s growing missile and nuclear threats.

Yoon: THAAD deployment
Yoon has openly endorsed the idea of additionally deploying the Terminal High Altitude Area Defense (THAAD) batteries, which employ hit-to-kill technology and intercept incoming ballistic missiles at altitudes between 40 and 150 km.

Yoon emphasized the necessity of the THAAD system to destroy ballistic missiles fired toward the Seoul metropolitan area with a lofted and high-angle trajectory.

“(The THAAD system) needs to be deployed in the metropolitan area as there would be high chances that North Korea would fire missiles at a high angle when targeting the metropolitan area,” Yoon said.

Yoon went on to say that a location for additional deployment requires military consideration, and therefore the matter could be further examined in the future.

The presidential hopeful also underscored the significance of the THAAD system as a component of South Korea’s “multilayered” missile defense system.

Yoon has promised to speed up establishing and completing the indigenous three-axis missile defense system which originally consisted of the Kill Chain, the Korea Air and Missile Defense (KAMD), and the Korea Massive Punishment and Retaliation (KMPR). 

But the Moon Jae-in government has renamed the triad to the “Nuclear-WMD Response System” and incorporated the Kill Chain and the KMPR into a “strategic strike system.“

Lee: Homegrown L-SAM development
Lee, antithetically, proposed the plan to expedite the development of indigenous long-range surface-to-air missiles (L-SAM), which can destroy ballistic missiles at an altitude of 40 km or above.

Lee put an emphasis on advancing the homegrown missile defense system rather than purchasing THAAD batteries from Washington, elucidating that Seoul plans to complete the development of L-SAM in two or three years.

“My view is that we can sufficiently establish a defense system with South Korea’s own technology and capabilities,” Lee said, expressing concern over Chinese backlash on any further THAAD deployment.

In return, Yoon pointed out that it would take a considerable time to deploy L-SAM, which is still under development.

Lee also pointed to the necessity of independently building a nuclear-powered submarine. To that end, Lee said he will seek to amend the nuclear cooperation agreement to enable South Korea to acquire the required technology.

Moon Jae-in government’s ‘Three Noes’
But more importantly, the discrepancy between Lee and Yoon in choosing a kill vehicle stems from their conflicting views on the South Korea-US alliance and China policy.

Lee said he views the Moon Jae-in government’s “Three Noes” policy is “appropriate” in light of the economic cooperation with China.

After a diplomatic clash over the THAAD deployment, Seoul in 2017 promised Beijing that the country would not deploy additional THAAD batteries, integrate into the US-led regional missile defense system, nor participate in trilateral military cooperation between South Korea, the US, and Japan.

Lee underlined that South Korea should continue to develop a “strategic cooperative partnership” with China due to the country’s high-level dependence on trade.

“It is desirable to maintain an amicable relationship as far as possible since we should not and cannot get out of economic cooperation,” Lee said, pointing to the significance of preventing economic losses previously caused by the THAAD deployment.

Lee accused Yoon of “taking advantage of anti-China sentiment” in South Korea for his “political gains.”

South Korea-US alliance vs. balancing act
During the TV debate, Lee admitted the necessity and importance of strengthening the South Korea-US security alliance and upgrading it into a “comprehensive alliance” as agreed by President Moon Jae-in and US President Joe Biden.

But Lee suggested that he will maintain the Moon Jae-in government’s balancing act between Beijing and Washington.

When asked by a moderator to choose the first person to meet among the leaders of the US, China, Japan, and North Korea after being elected as president, Lee refused to answer.

Lee said his decision will take into account the efficiency and usefulness of a meeting, underscoring the significance of ”balanced“ and “practical diplomacy centered on national interests.”

In response to the same question, Yoon said he will first meet US President Biden.

Yoon went on to say that he will then have separate meetings with Japanese Prime Minister Fumio Kishida, Chinese leader Xi Jinping, and North Korean leader Kim Jong-un in that order.

“In my opinion, the priority is to restore the relationship with the US and Japan which have been fractured … during the period of the Democratic Party’s ruling,” Yoon said, denouncing the Moon Jae-in government’s inclination toward China and North Korea.

Yoon also reinstated his commitment to “further strengthen the South Korea-US alliance and reinforce the (US) extended deterrence.”

Extended deterrence is the US’ commitment to deter or respond to adversary coercion plus nuclear and non-nuclear military attacks on US allies and partners. The US nuclear umbrella is one means the US offers to achieve extended deterrence.

Yoon also dismissed the possession of nuclear weapons and NATO’s nuclear-sharing mechanism, given that the two options breach the Nuclear Non-Proliferation Treaty as well as complicate nuclear negotiations with Pyongyang.

The candidate elucidated that the options will rather lead to “acknowledging North Korea’s possession of nuclear weapons” and shifting the negotiation agenda from denuclearization to “nuclear disarmament.”