If South Korea faces an imminent attack from nuclear-armed North Korea, what is the most viable military option to defend the country and prevent incalculable and irreparable damage?

Seoul-based experts say South Korea would have no option but to consider launching a preemptive strike, although the anticipatory use of force would come with a certain price. That price could far outweigh potential gains, experts say.

But the bigger problem is Pyongyang‘s mounting artillery, missile and nuclear threats that not only make a preemptive strike plan more indispensable, but also restrain Seoul’s preemptive strike capabilities.

As North Korea’s nuclear and missile prowess is proportional to the threat of preemptive nuclear attack, South Korea cannot and should not give up on a preemptive strike plan.

The correlation clearly depicts South Korea’s deteriorating security situation and the conundrum concerning a preemptive strike that the country has long wrestled with.

Heated debate on preemptive strike
A preemptive strike has drawn public attention in Seoul, as the issue is at the center of political disagreement with around 40 days left until the presidential election.

The main opposition People Power Party’s presidential candidate Yoon Suk-yeol this month raised the necessity of launching a preemptive strike with the Kill Chain system, when asked how to prevent missile threats by North Korea.

Yoon said it was virtually impossible to intercept a missile carrying a nuclear weapon if it travels at a speed of Mach 5 or greater, reaching the Seoul area within just a minute.

The campaign of the ruling Democratic Party of Korea’s Lee Jae-myung launched blistering criticism and maintained that “there has been no leader who directly and publicly addressed a preemptive strike on North Korea.” The camp said a preemptive strike was an “extremely risky scenario” given that “there are high chances that it would turn into an all-out war.”

But not surprisingly, South Korea has continued to develop and secure independent preemptive strike capabilities while developing the Kill Chain system as part of a three-axis system since 2012. 

The triad consisted of the Kill Chain, the Korea Air and Missile Defense and the Korea Massive Punishment and Retaliation, which has since been renamed the “Nuclear-WMD Response System.”

The Moon Jae-in administration has incorporated the Kill Chain and the KMPR into a “strategic strike system,” which seeks “deterrence by both denial and punishment to deter and counter omnidirectional, asymmetric threats,” the 2020 Defense White Paper said. 

To that end, the military has continued to build “forces equipped with long-distance surveillance capabilities and precision strike capabilities.”

Preemptive vs. Preventive strike
Then, what is a preemptive strike? And what is its significance?

In general, a preemptive strike is recognized as an anticipatory use of force to defend a country against a perceived imminent but not actually armed attack. 

The US Defense Department defined a preemptive strike as an “attack initiated on the basis of incontrovertible evidence that an enemy attack is imminent,” as part of the Bush Doctrine of the George W. Bush administration.

But a preventive strike is initiated based on the belief that “military conflict, while not imminent, is inevitable, and that to delay would involve greater risk.”

The Six-Day War between Israel and neighboring Arab states in June 1967 is a rare example of such a preemptive attack, conducted by Israel. The US invasion of Iraq in 2003 was a preventive war to destroy Saddam Hussein’s purported weapons of mass destruction.

It is crucial to recognize the difference between a preemptive and preventive strike. A preemptive strike can be justified as an act of preemptive self-defense under certain circumstances, although there has been no universal and undisputed yardstick for judging the legitimacy.

Article 51 of the UN Charter stipulates that the charter does not proscribe the “inherent right of individual or collective self-defense if an armed attack occurs against a Member of the United Nations.”

But as there have been divergent interpretations of an armed attack, questions still remain on the morality and legitimacy of a preemptive war.

Feasibility of preemptive strike plan
There are multitudinous factors that restrain Seoul’s preemptive strike capabilities, including tardy progress in the transfer of wartime operational control.

Yang Uk, an associate research fellow at the Asan Institute, pointed out that there are three main pillars -- “detect first, decide first and strike first” -- that would enable South Korea to launch a preemptive attack against North Korea’s imminent attacks.

But South Korea’s weakness in intelligence, surveillance and reconnaissance, or ISR, capabilities against North Korea and its overdependence on the US’ ISR assets pose major hindrances.

More importantly, the South Korean president’s ability to decide to launch a preemptive strike, which would entail a heavy political burden, is also a key determinant.

“The stage of making a decision is also greatly instrumental,” Yang said. “This is not just a military determination, but both a military and a political resolution.”

Park Won-gon, a professor of North Korean Studies at Ewha Womans University, pointed to North Korea’s development of solid-propellant missiles with enhanced survivability as one of the major restraints.

Solid-fuel ballistic missiles can be stored, transported and fired with a shorter-preparation time from transporter-erector-launchers, giving South Korea only a 15-minute window to respond.

“Seoul has to detect signs (of imminent attacks), identify targets, make a decision and launch a strike within less than 15 minutes,” Park said. “It would be immensely difficult to carry out an attack on the actual battlefield.”

Additionally, North Korea’s pursuit to miniaturize nuclear warheads and develop and variegate dual-capable missiles able to deliver both conventional and nuclear payloads has made it extremely challenging for Seoul to discern whether Pyongyang intends to launch nuclear attacks.

“Seoul would be unable to identify whether missiles deliver conventional or tactical nuclear warheads even when signs of imminent missile launches are detected,” Park said, pointing to the KN-23 and KN-24 short-range ballistic missiles launched this month as an example of newly developed dual-capable missiles.

The geographical proximity between the two Koreas and thousands of artillery and rocket systems deployed across the full length of the Demilitarized Zone would impose another restriction, said Choi Hyun-ho, a military columnist at the JoongAng Ilbo.

American think tank Rand Corp. estimated that North Korea has deployed 4,800 medium-range artillery pieces with a maximum range of 25 kilometers across the DMZ in its “North Korean Conventional Artillery” report in 2020. 

Approximately 950 long-range artillery pieces that can reach Seoul with its population of around 10 million people and the surrounding area are deployed near the North’s city of Kaesong.

The US think tank warned that North Korean artillery strikes “could cause thousands of casualties in just a minute and more than 100,000 in an hour.” 

“We must completely and simultaneously neutralize medium- and long-range artillery threats if we launch a preemptive strike. But it doesn’t seem feasible,” Choi said.

Choi also pointed out it is practically improbable to incapacitate or destroy innumerable missiles in North Korea at one go.

North Korea’s strategic placing of long-range missiles along its border with China would also aggravate South Korea and the US’ decision-making process.

“Pyongyang has deployed most of the long-range missiles along the North Korea-China border, which makes it extremely tough and complicated for South Korea and the US to launch a preemptive strike,” Choi said.

“In a word, North Korea has multifarious options (to deter South Korea’s preemptive strike),” Choi added. “But Seoul has countless constraints.”

Sole military option against N.Korea’s attacks
Then, should South Korea abandon a preemptive strike plan?

Experts view a preemptive strike as the sole military option in the case of an imminent attack from Pyongyang, especially since North Korea has diversified its delivery vehicles to carry nuclear weapons.

“It is not feasible yet. But we have to prepare for a preemptive strike as there are no other military options,” Park said. “It is inevitable and imperative to develop the feasibility (of the plan).”

Yang underlined that a preemptive strike would be the one and only option against North Korea’s imminent asymmetric and nuclear attacks on South Korea, which would inflict irreparable and incalculable damage.

“If North Korea uses weapons capable of delivering nuclear warheads, we ought to assume that the country will launch a nuclear attack,” Yang said. “North Korea should take the risk as a nuclear-armed state.” 

Political leader’s public endorsement
But opinions diverge as to whether it is appropriate for a presidential candidate to explicitly support a preemptive strike plan.

Kim Young-jun, a professor at the Korea National Defense University, pointed to the peril of Yoon capitalizing on a preemptive strike for “political gains” in the electoral race.

An influential politician or a political leader’s public endorsement of a preemptive strike would cause disadvantages to their foreign policy direction, particularly at this point. In short, the costs of such a move would far exceed its benefits.

“Presidential candidate Yoon Suk-yeol limits his diplomatic options at a time when South Korea is preparing for the next five years,” Kim said. “Yoon seems to be seeking to win people’s votes, but he is now giving up his diplomatic tools.”

Kim explained the US and the former Soviet Union had not threatened each other with preemptive strikes during the Cold War, although both sides prepared for a plan.

Park underscored that Seoul should face up to reality. Pyongyang has pursued development of dual-capable missiles and tactical nuclear weapons, as well as more survivable and maneuverable ballistic missiles that can penetrate and incapacitate missile defenses.

South Korea should look at the big picture and have a comprehensive discussion of North Korea’s mounting missile and nuclear threats, rather than clouding the picture and making a preemptive strike a political issue.

Park pointed out that it was essential to assess North Korea’s intention and threats and South Korea’s missile defense capabilities, and seek ways to reinforce military capabilities at this juncture.

“It is very regrettable that the ruling and opposition political parties argue over the statement while such discussion is absent.”

Nonetheless, experts say stressing the need to launch a preemptive strike to deter North Korea’s existential and rapidly growing threats to defend the country is unavoidable.

“We are asking the question equivalent to whether the US president can press a nuclear button in case of nuclear attacks by an enemy,” Yang said.

“No one wants to go ahead with the option. But at the end of the day, we will be attacked or face another war unless we demonstrate our capability of launching (a preemptive) strike at any moment.”

By Ji Da-gyum (dagyumji@heraldcorp.com)