North Korea’s fourth nuclear test has provoked renewed calls among leading South Korean lawmakers for South Korea to obtain its own nuclear deterrent force. Grabbing headlines most recently was the ruling Saenuri Party’s floor leader, Representative Won Yoo-chul, who reportedly said shortly after the nuclear test that “North Korea has been pointing a gun at our head for years. It’s time we stop defending ourselves with a mere sword and have nuclear weapons to challenge its destructive nuclear weapons.” Such sentiments are not new and reflect a long-running internal debate on how to deal with its northern neighbor. Nevertheless, with each successive North Korean nuclear detonation, calls by increasingly prominent ROK leaders to nuclearize have become more explicit. Public opinion has also become more supportive of a nuclear-armed South Korea.
Although Representative Won’s statement is similar to calls by conservative lawmakers following North Korea’s 2013 test, his prominence as the number two ranking official of President Park Geun-hye’s party is noteworthy. Also significant was his apparent rebuke of conventional weapons as adequate to deter the North.
Nuclear supporters in South Korea also argue that North Korea would be more amenable to disarmament talks if faced with a nuclear armed adversary across the DMZ. Kim Eul-dong, a Saenuri Party Supreme Council member, said at a January 7 party meeting that “denuclearizing the Korean Peninsula can be made possible only if we own tactical nuclear weapons [emphasis added].”
The South’s pro-nuclear camp has popular opinion behind it as well. According to a poll conducted by the ASAN Institute for Policy Studies following the North’s 2013 nuclear test, 66.5 percent of South Koreans said they “supported” or “strongly supported” acquiring nuclear weapons, up from 56 percent in 2010. This sentiment is hardening as well, with the number of those who say they “strongly support” a nuclear South Korea more than doubling between 2010 (12.6 percent) and 2013 (30.1 percent). ASAN also found in 2012 that only 48 percent of South Koreans have faith in the U.S. nuclear umbrella, down 7 percent from 2011. With the international community’s apparent inability to roll back North Korea’s nuclear development, these trends seem likely to continue.
Thus far, President Park has held the line against these pressures, warning in a January 13 address against “breaking our commitment to the international community.” Park’s statement is indicative of the main South Korean concern about acquiring nuclear weapons: complicating its relations with the United States and China and risking international sanctions. Nevertheless, a future ROK president could easily see things differently. The Nuclear Non-Proliferation Treaty, to which South Korea is a party, allows a government to withdraw if it “decides that extraordinary events…have jeopardized the supreme interests of its country.” Many South Koreans already see their country in a unique security situation.
South Korea already has a robust nuclear industry that could theoretically feed a nuclear weapons program. Its nuclear reactors produce large quantities of spent fuel that could be reprocessed into plutonium. Although it currently lacks reprocessing infrastructure, developing this capability is well within reach of South Korea with its ample resources and deep bench of nuclear expertise.
Should South Korea eventually choose to build a nuclear arsenal, it would do so in way that fits its geographic and strategic situation. Seoul would have good reason to keep its doctrine for nuclear use limited given its geographic proximity to the DPRK, and the possibility that any all-out conflict would result in a reunified peninsula. Furthermore, there would be little need to target the North’s vastly inferior conventional forces, save perhaps for DPRK artillery positions in range of Seoul. One possibility would be small, lower yield nuclear weapons, aimed at eliminating DPRK nuclear forces in a crisis. This would also seem to align with Representative Kim Eul-Dong’s specific reference to “tactical” nuclear weapons in her comments on January 7.
Such a posture would have South Korea leaning toward a counterforce capability, which could possibly make nuclear employment on the peninsula more probable if North Korea were to continue its pattern of provocative behavior. On the other hand, it could provide a potent and credible deterrent against North Korean provocation, greatly moderating its behavior.
This is neither a prediction nor endorsement of South Korea taking this path. In fact, these are possibilities that few would like to see evolve. However, South Korea has serious security threats, and its continued commitment to nonproliferation in the face of those threats should be acknowledged. It is therefore important that the United States continue to take meaningful and concrete actions to demonstrate its commitment to South Korean security. Working toward a more robust missile defense in the region and for the U.S. homeland is one way to buttress eroding confidence in U.S. assurances. The United States should also continue working closely with South Korea to ensure both nations have robust conventional strike capabilities and adequate intelligence to quickly cripple Pyongyang’s ability to employ its nuclear weapons, should the need arise. Reaffirming U.S. extended deterrents in these ways could go a long way to ease South Korea’s serious security concerns, and help it maintain its nuclear abstention.
Ian Williams is an associate fellow in the CSIS International Security Program, and associate director of the CSIS Missile Defense Project.