North Korea is again ramping up its nuclear weapons tests, prompting alarm from the United States and Washington’s East Asian allies. Following years of escalation with its Northern counterpart, South Korea has developed a multi-layered doctrine to control for the imminent possibility of a nuclear conflict with Pyongyang. One of the core components of South Korea’s strategy is the ‘Kill Chain’—here is what it means, and how it figures into Seoul’s broader plan to counter the growing threat from North Korea’s nuclear arsenal.

The “Kill Chain” concept gained international attention following its appearance in a 2012 white paper. The paper stated that the “the ROK [Republic of Korea] military will decisively strike not only the origin of enemy provocation, but also the command and support forces behind the provocation.” The paper added that “the ROK military is not only reinforcing its precision surveillance, target acquisition, and precision strike capabilities in the Northwest Islands and the surrounding areas, but is also significantly strengthening its ‘immediate retaliation forces’, including air defense and anti-missile defense capabilities, as well as airborne and standby forces.”

Kill Chain is, at its core, a detection and preemption strategy. According to this plan, South Korea will leverage its formidable network of intelligence and surveillance assets to continually monitor North Korean political developments and military movements. Upon receiving confirmation that the Democratic People’s Republic of Korea (DPRK) is preparing to attack, the ROK military will initiate a series of rapid precision strikes against key North Korean military assets; these can include long-range artillery installations as well as any and all DPRK missile sites, both nuclear and conventional. To control for the risk of further escalation, Kill Chain will not target North Korea’s leadership or non-military infrastructure.

Then there is the retaliatory variant of Kill Chain, intended as a response to a North Korean nuclear or major conventional strike. Dubbed Korea Massive Punishment and Retaliation (KMPR), the plan covers the same ground as Kill Chain but adds a decapitating strike against DPRK’s political and military leadership that is aimed at producing regime change. According to South Korean sources, KMPR reportedly involves the total destruction of Pyongyang. “Every Pyongyang district, particularly where the North Korean leadership is possibly hidden, will be completely destroyed by ballistic missiles and high-explosive shells as soon as the North shows any signs of using a nuclear weapon. In other words, the North’s capital city will be reduced to ashes and removed from the map,” a source told South Korea’s Yonhap News Agency.

Although experts have argued that South Korea previously lacked the resources to unilaterally execute a sweeping preemptive strike along these lines, ROK’s reconnaissance and military capabilities have grown by leaps and bounds over the past decade. Still, the Kill Chain doctrine has prompted some lingering concerns. The plan hinges on a timely and accurate intelligence assessment that not only points to an imminent North Korean attack, but is able to identify all the relevant sites to be destroyed. The verifiability threshold must be high enough to eliminate the possibility of a mistake, but low enough to ensure a sufficient window for a full response. Within minutes, ROK’s military and civilian leadership will have to make a series of rapid decisions authorizing the strikes. The ROK must then be ready and able to defeat all possible North Korean counterstrikes against Seoul. The Kill Chain plan can veer off course at any point in this long sequence of events, potentially with disastrous consequences for the South Korean side.

Nevertheless, Seoul at least has some cause for cautious, long-term optimism. Many of these implicit risks continue to grow smaller in proportion with South Korea’s rapidly expanding capabilities; if nothing else, the successful execution of Kill Chain is substantially more feasible today than when it was first conceived.

Mark Episkopos is the national security reporter for the National Interest.

Image: Reuters.