Abstract
This paper investigates whether or not enduring rivals adopting non-proliferation policies permanently abandon their nuclear weapons programs. The author's argument is that enduring rivalry is better understood as fluctuating between increasing and decreasing tension phases; the fluctuation is determined by security threats and international status. Domestic factors such as regime type and economic conditions, however, have little influence on the rivalry fluctuation.
The paper also argues that enduring rivals' nuclear proliferation and non-proliferation policies correspond to these different rivalry phases. Enduring rivals initiate nuclear weapons programs when the rivalry passes an increasing tension phase and suspend, rather than give up, the programs during the decreasing tension phases and as long as the rivalries are not terminated. Enduring rivals may give up their nuclear weapons programs only when the causes of rivalry cease to exist, such as South Africa. This argument is tested in the context of the Korean enduring rivalry, and it is found that both South and North Korea initiated or reactivated their nuclear weapons programs when their security threat perceptions were intensified, but suspended the program when their security threat perceptions were mitigated.
The results suggest that while it is not unreasonable to question the credibility of nuclear-capable enduring rivals' non-proliferation policies, the non-proliferation regimes need to address security guarantees and/or regional security arrangements instead of focusing on legal and technical restrictions.