South Korean Perspective

Deterrence, NPT and the Two Koreas

A South Korean View on Further Cuts in Nuclear Weapons

In April 2009, during his visit to Prague, President Obama announced his plan for “a world without nuclear weapons.” Through a series of negotiations, the United States and Russia reached an agreement to reduce nuclear weapons to 1,550 each—the New START Treaty. Four years later in Berlin, Obama stated, “we can ensure the security of America and our allies, and maintain a strong and credible strategic deterrent, while reducing our deployed strategic nuclear weapons by up to one-third.” Furthermore, he mentioned that the United States will work with NATO allies to seek bold reductions in tactical nuclear weapons in Europe. Both politically and morally, it is difficult, or “incorrect,” to argue against a world without nuclear weapons.

However, the issue of the credibility of US extended deterrence, the nuclear umbrella, toward its allies should be tested against the constantly changing strategic landscape in East Asia and the perceptual/psychological, if not really operational, aspect of nuclear deterrence; that is, whether US allies and a potential aggressor and proliferator such as North Korea believe in the robustness of a new US nuclear posture with fewer strategic and tactical nuclear weapons following the desired changes in coming years.

As a trusted ally and responsible signatory to the NPT, South Korea would, in principle, support Obama’s plan of further reduction of strategic nuclear weapons, gearing toward a world without nuclear weapons. Yet, with the advances in North Korea’s WMD capabilities, over the past several years, it has become very much concerned about the credibility of US extended deterrence. To address these concerns, the United States and South Korea established the Extended Deterrence Policy Committee (EDPC) to develop and implement more concrete and reliable deterrence measures. It is reported that, in EDPC meetings, the two have primarily focused on conventional deterrence measures, excluding the other components—nuclear and missile defense. Thus, it is possible to say that the intended reduction of US strategic nuclear weapons by one-third would not affect the US extended deterrence posture seriously.

A problem may arise, however, when it comes to the reduction of tactical nuclear weapons. After witnessing three nuclear tests by North Korea, unlike its government’s position, more than 65 percent of the South Korean public supports the reintroduction of US tactical nuclear weapons as reassurance of the US commitment to the defense of South Korea. For them, the reduction of tactical nuclear weapons in Europe means that there is very little chance of redeployment of US tactical nuclear weapons on South Korean soil, raising concern that US extended deterrence to South Korea is neither comprehensive nor proportional, reviving the once unthinkable notion of South Korean development of an independent nuclear capability.

Another, maybe more serious, problem is how North Korea interprets Obama’s reduction plan. Just a few hours after the Berlin address, the White House announced, “the United States will only consider the use of nuclear weapons in extreme circumstances [emphasis added] to defend the vital interests of the United States or its allies and partners.” What constitutes “extreme circumstances?” What is the North Korean interpretation of this statement? It might interpret the US position to mean no use of nuclear weapons against North Korea so long as the North’s provocation does not cross the threshold of “extreme circumstances.” If so, the probability of conventional provocations by North Korea might increase.

After reading Obama’s statement and the White House fact sheets, North Korea might feel it even more advisable to advance its nuclear capabilities to be recognized as a nuclear power. It may think that the United States appears to be quite confident of meeting its nuclear challenge; so, to achieve its goal of being accepted as a nuclear power, North Korea might feel it necessary to develop more advanced and deadlier weapons. In addition, North Korea might feel safer and stronger by having a more reliable deterrence posture of its own against the United States if it possesses more nuclear weapons with longer-range delivery vehicles. The US reduction in its strategic nuclear arsenal and tactical nuclear weapons and its reluctance to use nuclear weapons might give rise to unintended misinterpretations. Consequently, South Korea may become more vulnerable to North Korean threats, and the credibility of US extended deterrence would be undermined.

Even under the increasing North Korean nuclear threat, South Korea has remained a non-nuclear power, relying on US extended deterrence. As a responsible signatory to the NPT, it welcomes the noble goal of “a world without nuclear weapons” and argues for a “nuclear-free Korean Peninsula.” Yet, to sustain that posture its security concerns must be carefully addressed. The US intention to reduce tactical nuclear weapons might possibly ignite a debate over an independent South Korean nuclear capability, even though South Korea is very unlikely to go nuclear. To cool such a debate, the United States and South Korea should enhance conventional deterrence capabilities dramatically to the level that North Korea fears. By sending the wrong signal to North Korea and leaving a chance of misunderstanding, strategic stability, including stability in crises, can be seriously challenged. To maintain peace and stability, and to achieve a nuclear-free Korean Peninsula, it is desirable to take a cautious approach, with all options left on the table for some time.