Following North Korea’s most recent nuclear test on February 12th, conservative officials in the South have resumed calls for the return of U.S. tactical nuclear weapons to the peninsula.
“The only way to defend our survival would be to maintain a balance of terror that confronts nuclear with nuclear,” said Representative Shim Jae-cheol at a National Assembly meeting, before recommending the redeployment of nonstrategic nuclear weapons (NSNWs) to his country. Meanwhile other officials have recommended an independent South Korean nuclear deterrent.
These calls from ROK conservatives may not come as a surprise: Similar exhortations followed previous North Korean provocations. What’s more, this latest iteration of North Korean bellicosity has included some especially ominous rhetoric. DPRK officials have suggested that U.S.-ROK joint military exercises could ignite a war, and that South Korea may meet its “final destruction.”
There is no question that the South has reason to be anxious regarding its security. But this latest round of security challenges on the peninsula begs the question: Why do some South Koreans want tactical nuclear weapons, and what would they do for ROK security? Specifically, how would they reinforce the U.S. nuclear umbrella?
American tactical nuclear weapons were withdrawn from the Korean peninsula in late 1991 as part of President George H.W. Bush’s Presidential Nuclear Initiative. Shortly thereafter, the ROK and DPRK signed a Joint Declaration of commitment to a nuclear weapons-free Korea. The North’s subsequent development of a small, independent nuclear stockpile upended that agreement. The DPRK also maintains that the ROK’s continued alliance with the United States violates the pact, as the South remains under the U.S. nuclear umbrella. If the South were the victim of a major attack, the United States could defend it using its strategic nuclear arsenal of homeland-based intercontinental ballistic missiles (ICBMs),bombers and sea-based submarine launched ballistic missiles (SLBMs).
It is not surprising that many in the South feel that they have gotten short shrift as the North has continued to develop nuclear and missile capabilities: After agreeing to the withdrawal of U.S. NSNWs, they now face a nuclear-armed, highly-provocative neighbor to the North. And despite the fact that the United States goes to great lengths to assure the ROK of its continued conventional and nuclear commitment to its security, there is skepticism in the South as to whether American nuclear assistance would be forthcoming in a time of crisis. In a 2012 Asan Institute survey, only 48 percent of South Korean respondents said that they believed the United States would employ its nuclear forces in response to a nuclear strike by the DPRK on South Korea. A significant number of South Koreans, including high-level officials seem to believe that the return of NSNWs would help to fill this perceived strategic gap.
One reason for continued South Korean interest in tactical nuclear weapons is their role in so-called “de-coupling.” In any alliance that involves extended nuclear deterrence, there is a fundamental credibility problem: Why would a nuclear state like the United States use those weapons on behalf of South Korea, and invite retaliation on its own homeland? Put differently, why would an American president ever voluntarily trade Washington for Seoul? For the time being, the DPRK probably doesn’t have the missile capabilities to reach the continental United States. If it acquires them, however, and the North actually has the ability to hold U.S. cities at risk, this dilemma could be of even greater concern.