Several years ago, there was a nasty little dispute in international relations over the utility of nuclear weapons for crisis bargaining and compellence. Matthew Kroenig purported to show that in a sample of 20 crises, the side with the larger nuclear arsenal—and thus presumably capable of dominating the escalation ladder—tended to prevail (Matthew Kroenig "Nuclear Superiority and the Balance of Resolve"). Todd Sechser and Matthew Fuhrmann—by chance in the same issue of the journal International Organization—published a related research note arguing that the possession of nuclear weapons did not increase the effectiveness of coercive threats (Todd Sechser and Matthew Fuhrmann "Crisis Bargaining and Nuclear Blackmail"). Their explanation for this somewhat counterintuitive result is the fact that nuclear weapons are not particularly useful for seizing assets of interest—as opposed to deterring—and their actual use would risk massive backlash from the international community. The controversy was replete with debates over theory, methods and data, summarized neatly in several posts at the Duck of Minerva (Kroenig Duck of Minerva; Secsher and Fuhrmann Duck of Minerva 1; Sechser and Fuhrmann Duck of Minerva 2). But the debate was hardly academic. Kroenig—who believes that nuclear weapons have real value—wrote a book saying we should attack Iran. This position endeared him to some but generally met with serious doubts in the IR community (Steve Walt is exemplary).
Given the small number of cases, the statistical results need to be taken with a serious grain of salt, with some detailed consideration of possible mitigating circumstances. For example, in the Korean case North Korea now enjoys nuclear superiority vis-à-vis the South, but in the context of extended deterrence on the part of the US. So will the possession of nuclear weapons change North Korean behavior toward the South or continue to be constrained by American nuclear dominance?
Bob Carlin and Bob Jervis--a pretty formidable team--tackle these issues in a new paper in the North Korea's Nuclear Future series at SAIS. In fact, they point out that there are three related but subtly different questions:
- “Will possession of a larger arsenal of deliverable nuclear weapons change the North’s propensity to engage in behaviors that could trigger a confrontation?
- Will possession of a larger arsenal of deliverable nuclear weapons change the North’s behavior during a confrontation, whatever its origins?
- Will possession of such a capability cause the North to reexamine and change its overall strategy and goals, i.e., will deterrence theory as understood by the United States and others become central to Pyongyang’s thinking, or will it discard such concepts entirely for a new, dangerous, and essentially destabilizing approach?”
On the first question, their response—based on both theory and evidence—is skeptical; the shelling of Yeongpyeong Island is one possible exception, but they note that North Korea took such risks prior to its possession of nuclear weapons and the shelling of Yeongypyeong probably had domestic political roots. To the second more tactical question, they hedge a bit more. It is hard to see a clash along the Northern Limit Line escalating into nuclear use unless the regime thought it faced a large-scale intervention aimed at its defeat and ouster—highly unlikely events. But they do not rule out that nuclear weapons may make North Korea more risk prone vis-à-vis Japan and the South.
With respect to the last strategic question, they note that “of the eight countries that have developed nuclear arsenals, none has so far decisively altered its fundamental calculations or stepped beyond the bounds of rational action.” Carlin and Jervis do make a point that this blog has made repeatedly, however: “an increasing stockpile both indicates a strong commitment to remain a nuclear power and builds bureaucratic and domestic interests that are likely to maintain a program, and indeed move it further to the forefront.” But they caution that an increasing arsenal will not necessarily lead to changes in intent or behavior and they are even cautious about whether the window has closed for negotiations.
But their main conclusion is that under any of the plausible scenarios of the growth of North Korea's arsenal, not much in North Korea’s actual behavior is likely to change. That is not necessarily a good thing since the North was unpredictable to begin with. But at least it means that the angst that expanding capabilities would lead to a fundamentally new course is probably unwarranted.