Extremists and unconventional weapons: examining the pursuit of chemical and biological agents

ABSTRACT

In this study, we examine the individual-level characteristics of extremists’ pursuit of chemical/biological (CB) agents. Using three different maximum likelihood estimation techniques, we identify three key findings. First, older extremists are more likely to pursue CB than younger extremists. Second, extremists who are jobless or students are more likely to pursue CB than employed extremists. Third, Islamist, far-right, and far-left extremists are less likely to pursue CB than single-issue extremists. We do not find any evidence that gender or education have an effect on whether an extremist will pursue CB agents. Since there has been little quantitative examination of unconventional weapon choices among violent extremists, this study makes an important contribution to the literature on CB adversaries.

KEYWORDS:

• Terrorism
• extremism
• CBRN
• unconventional weapons

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.

Acknowledgments

The authors would like to thank Gary Ackerman, Markus Binder, Rebecca Bryan, Dennis Foster, and Patrick James for their invaluable contributions to this research, as well as the two anonymous reviewers and University at Buffalo's Department of Political Science. The authors are solely responsible for any errors.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes on contributors

Thomas R. Guarrieri is an Assistant Research Scientist at the National Consortium for the Study of Terrorism and Responses to Terrorism (START) and the Director of Undergraduate Studies for the University of Maryland's Terrorism Studies Department. He holds a Ph.D. in Political Science from the University of Missouri.

Collin J. Meisel is a researcher with the Frederick S. Pardee Center for International Futures' Diplometrics project, which gathers and analyzes data on issues related to international security. He holds an M.P.P from Georgetown University.

Notes

1 Many of the limitations regarding additional control variables are a result of the paucity of data for CBRN actors. There are numerous additional variables related to internet usage, gun ownership, personal relationships, and specific policy beliefs (to name a few) that could also be predictors of pursuit of unconventional weapons. Unfortunately, we were not able to find available data for these variables.

2 In the study for India, findings are not to the point of statistical significance when controlling for other factors.

3 According to the study, 26% of perpetrators had criminal motives.

4 For a non-leader member of a group, we only include cases in the sample drawn from CABNSAD where they are coded as a decision-makers to pursue CB since this is our theoretical population of interest. Please see Footnote 6 for additional information about this distinction.

5 We verified this by comparing the two datasets looking for matched names, as well as key word searches through the PIRUS data for CB-related terms and phrases. We coded four individuals with unknown, but possible, CB or RN weapon pursuits as unknown.

6 The CABNSAD codebook defines decision-makers in the following manner: ‘Perpetrator was involved in the decision to pursue/use CB. In the case of an organization, this may include organizational leaders.’ For organizational leaders, the dataset's creators add:

As a general principle, organization leadership figures are included in CABNSAD where there is some indication that they played a part in decision-making related to the development or use of CB weapons. In the case of weakly structured organizations, or organizations in which the pursuit of a CB capability was undertaken on the independent initiative of a lower-level figure it may be inappropriate to include apex leadership (National Consortium for the Study of Terrorism and Responses to Terrorism, 2017, p. 9).

7 Note that once PIRUS researchers had assembled a complete set of cases, they then sampled from that set randomly.

8 However, given different cultural environments, there may be structural conditions within different states that affect extremist weapon choice. Given an already small sample of cases in the data, we do not investigate structural factors, but we anticipate that our theoretical expectations regarding individual-level demographic characteristics exclusively are generalizable to different countries.

9 This is not to say that gender is binary, but PIRUS and CABNSAD do not include data on extremists who identify as neither male nor female.

10 Given that the CABNSAD coding schema for education is less granular than PIRUS, we collapsed the PIRUS education categories to the four levels in CABNSAD, leaving the aforementioned four levels.

11 We also collapse the PIRUS employment categories into the CABNSAD categories with the slight alteration of reclassifying unemployed individuals as ‘jobless,’ which leaves open the possibility that an individual was illicitly, or informally, employed. The datasets also included a category for ‘retired’ but there were no individuals in our sample that were coded as being retired.

12 e ≈ 2.71828. The coefficients are exponentiated because the standard logistic regression output is expressed in log odds, or the natural log of the odds ratios.

13 Given the possibility that the relationship between Education and CB pursuit is non-monotonic and non-linear, as a robustness check we estimated an alternative model with indicator variables describing the impact of each education level relative to ‘High School or less.’ Consistent with our results, the education dummy variables were not statistically significant.

14 As a general guideline, variance inflation factors greater than 10 are considered to indicate high levels of multicollinearity, which can meaningfully impact statistical significance.

15 Note that this does not mean a variable's effect changes. However, the relative odds do change because of the change in the baseline category.

Additional information

Funding

This research did not receive external funding.