Some policymakers and analysts have expressed concern that weaknesses in responses to the coronavirus disease 2019 (COVID-19) pandemic will motivate terrorists to seek biological weapons. However, an examination of the Islamic State (IS) and al-Qaeda narratives about the pandemic reveals no causal relationship between the pandemic and any heightened interest in biological weapons. A review of the historical pursuit of biological weapons by the IS and by al-Qaeda reveals that both groups evinced some interest, but ultimately each employed conventional forms of attack instead. Despite limited IS use of chemical agents that challenged the taboo against the use of poison as a weapon, there are formidable hurdles that nonstate actors must clear to develop, produce, and use biological agents as weapons.

Although the prospect of the IS and al-Qaeda pursuing biological weapons is not zero, it is unlikely, given both the difficulties and the much easier and readily available alternatives that meet their deadly objectives. In the wake of the pandemic, several measures can enhance capabilities to address both public health and military challenges. These measures reduce the possibility of and improve the response to a future naturally occurring pandemic while also helping to deter, prevent, and respond to any possible terrorist acquisition and use of biological weapons. Focusing unduly on the potential, but unlikely, terrorist use of biological materials as weapons skews resources to unique military and counterterrorism measures and away from measures that are useful in both events. In the post-pandemic period, governments need to rebalance their efforts.