Lesser Evils?: Theorizing WMD Proliferation Beyond Nuclear Weapons

• In Event: Poster Session: International Security II

Abstract

Chemical and biological weapons (CBW) are often regarded as a potential “poor man’s atomic bomb” — a less effective substitute for nuclear weapons, pursued by states that desire, but are unable to acquire, a nuclear deterrent. Yet, empirically, we observe a variety of patterns of WMD pursuit, including chemical and/or biological weapons pursuit by states that show little or no interest in nuclear pursuit. In this paper, I develop a theory of states’ choices between proliferation options. I argue that these choices are shaped by the mix of external and internal security threats faced by a state’s governing regime, and by the resources and capabilities available to implement weapons programs. Chemical and biological weapons differ from nuclear weapons in two key aspects. First, CBW are generally perceived as less destructive, and therefore more credibly “useable” in lower stakes situations. This makes them an attractive tool for responding to domestic threats, while nuclear weapons are more applicable to external threats. Second, CBW are easier to acquire, requiring less scientific/technical knowledge, and relying more on difficult-to-regulate dual use components. Thus, states with limited implementation capabilities may pursue CBW as a substitute for a nuclear weapons program, or as a means of hedging against the failure of a nuclear program. Using cross-national time series data on WMD pursuit and possession, I find results consistent with this theory: internal security threats increase the risk of CBW pursuit relative to nuclear pursuit, while increased nuclear supply constraints increase the likelihood that multiple types of WMD are pursued simultaneously.

Author

• Miriam Barnum, University of Southern California