Recent mass casualty attacks in the United States have renewed a long-standing debate over the need for novel legislation to effectively prosecute domestic terrorism. Those who advocate for a new terrorism law argue that deficiencies in the US legal code present challenges to prosecuting domestic extremists, leading to unwarranted sentencing disparities in international and domestic terrorism cases. Critics of the proposal for a domestic terrorism law counter that the US legal code is sufficiently flexible for the courts to punish domestic extremists to the same extent as their international counterparts. Neither side, however, has produced an empirical assessment to support their claims. In this article, we address this research gap by analysing data on 344 US federal terrorism cases that were initiated between 2014 and 2019. We find that significant disparities are endemic to US federal terrorism prosecutions for three types of sentencing outcomes: length of incarceration; time spent on supervision upon release from prison; and the use of restrictive monitoring conditions. International terrorism defendants are more likely than domestic extremists to receive severe penalties for all three sentencing decisions even when controlling for criminal severity. Sentencing disparities in US federal terrorism cases are especially large when domestic extremists are prosecuted using common criminal charges, like weapons violations. We conclude with a discussion of what these findings mean for promoting judicial fairness in US terrorism prosecutions.

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Do targeted strikes against militant groups affect insurgent operations differently from terrorist operations? One of the reasons it is challenging for states to counter militant groups who simultaneously wage an insurgency and a terrorist campaign is that there are offsetting effects between counterinsurgency and counterterrorism. As both an insurgent group and a terrorist group, the Islamic State of Iraq and the Levant (ISIL) poses particular challenges to states. Since 2014, the United States and coalition allies have conducted thousands of targeted strikes against ISIL in Iraq and Syria as part of Operation Inherent Resolve (OIR). In this article, we examine the effects of targeted strikes against ISIL. Using a novel dataset of time-series observations from Iraq and Syria between 2015 and 2018, we examine the relationship between targeted strikes conducted under OIR and the number of insurgent and terrorist attacks conducted by ISIL. Our findings give empirical support to the theoretical argument that the same military strategy can have different effects on insurgency and terrorism.

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This paper proposes a new theory of non-state actors who engage in irregular warfare to seize territory and govern openly, called emerging-state actors. Emerging-state actors arise in periods of irregular conflict, such as the so-called Islamic State of Iraq and Syria (ISIS). The theory tries to answer “what is/was” the Islamic State because emerging-state actors differ notably from other non-state actors and insurgencies in irregular conflict. Causal diagrams as well as key propositions present the theory. Testing occurs against a system dynamics simulation called the “Emerging-State Actor Model” (E-SAM), loaded with the ISIS historical case in Syria and Iraq. Through experiments the simulation confirms evidence of emerging-state actor behavior as well as a range of contingencies showing their applicability. The novelty of E-SAM as a simulation for irregular conflict is its ability to handle multiple forms of conflict including political grievance, terrorism, insurgencies and emerging-state actors. E-SAM can also simulate multiple actors within each conflict: domestic and foreign state actors, local conflict actors, as well as different ethnographic groups. It can be parameterized with scenarios to simulate a variety of scenarios: ISIS in Libya, Boko Haram in Nigeria, Taliban in Afghanistan and even expatriated ISIS fighters returning to pursue new conflicts such as in Indonesia.

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Our research builds upon a theory of emerging-state actors. We look to apply the theory in analyzing intervention and containment policies to use against emerging-state actors, using the Islamic State of Syria & Iraqi (ISIS) as the case study. We show utility across four military applications of simulation: understanding, forecasting and responding to adversary and societal behavior; understanding enemy command and control structures; and analyzing, forecasting and planning courses-of-action (COA). To do this, we created two baseline scenarios—one replicating the historical foreign intervention against ISIS and a counter-factual where no foreign intervention occurred. We then conducted a suite of experiments on contemporary military intervention policies in isolation, combination, at different timing windows and under hypothetical “best case” conditions as well as operationally constrained. Insights of these experiments’ tests include the influence of ethnographic envelopes, timing windows, the importance of actor legitimacy and the marginally diminishing returns of combat actions. Finally, we test a policy based on emerging-state actor theory incorporating these insights against the contemporary policies, historical baseline and two falsification policies. The emerging-state actor COA performs significantly better than others. Our research contributes a simulation, called the Emerging-State Actor Model (E-SAM). This simulation includes military, economic, political, social and information aspects (known asDIME-PMESII simulations) for both researchers and military planners concerned with irregular conflict.

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This paper builds confidence in the terror contagion hypothesis that violent radicalization leading to predatory mass violence operates as a system. Within this system, the contingent values of key root causes create channels within which violent ideologies and terrorism emerge. We built a system dynamics simulation model capable of replicating historical reference modes and sophisticated enough to test the contingent values of these propositions. Of 16 propositions, we identified six root-cause propositions that must simultaneously exist, act in concert and explain the dynamics of their interaction which generate a terror contagion. Other propositions can strengthen or weaken an existing contagion but not eliminate it. We use an experiment to demonstrate how changing the contingent values of these propositions creates downward channels. This experiment helps reconcile the swarm vs. fishermen debate over the true root causes of violent radicalization. Within these channels, the contingent values can favor swarm or fishermen manifestations. The simulation and experimentation results enable the future development of the terror contagion hypothesis, provide a testing environment for research on violent radicalization, and provide a pathway to policy development in the combating of terrorism that arises from violent radicalization.

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This paper brings a systems engineering approach to policymaking in the context of violent radicalization. We test strategies to combat terrorism under the premise that violent radicalization is a complex system of social contagion resulting in terrorism. We built a simulation using DIME-PMESII military standards to replicate a terror contagion occurring over 10 years in both physical and online environments under optimal, realistic, and worst-case scenarios. We then tested antiterrorism, counterterrorism, and counter radicalization strategies as policy experiments in this simulation. These experiments identified four key dynamics relevant for developing policies to reduce terrorism. First, most well-known policies are ineffective in containing terrorism driven by social contagion. Second, strategies generating backlash can become worse than doing nothing at all. Third, perceived grievance determines the carrying capacity of terrorism in a system, allowing disrupted networks to regenerate. Fourth, variable public support may result in sharp secondary waves of violence under certain contingencies. Experimenting with our model, we explore effective ways to address the violent radicalization problem.

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What are the root causes of mass violence terrorism? Examining this question led to a novel hypothesis that violent radicalization leading to terrorism operates as a system of social contagion. A terror contagion exploits existing grievances and moral outrage well suited for radicalizing within a high-risk population. After a terrorist incident, media broadcasts of cultural scripts convey both a template violent ideology and a template method for mass violence. Radicalization can result when high-risk people receive these cultural scripts sharing self-similarity and notoriety bias to the perpetrator and their template ideology of grievance and outrage. Following the template method results in subsequent completed terror incidents creating their own media broadcasts, perpetuating the contagion. In this article, we share our methods, findings, and discuss the implications of a terror-contagion hypothesis. We describe experiments and testable predictions to build confidence in the terror-contagion hypothesis and our progress in them. © 2023 System Dynamics Society.

This report is a companion report to the publication “Government Responses to Asymmetric Threats: The State of the Literature on Counterinsurgency from 2002-2022,” which outlined general trends in government response to asymmetric threats as part of the Global Responses to Asymmetric Threats project. The latter is part of a broader research effort, Irregular Warfare Net Assessment Data Structure (IW-NEADS), that aims to create a data resource for assessment, analysis, and prioritization across various pillars of irregular warfare.  This report presents an overview of existing state of research on governments’ use of military lever of power in counterinsurgency (COIN) from 2002-2022.

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Consider the following pieces of a puzzle. Russia’s war against Ukraine has revealed stories about the heroic resistance efforts of Ukrainian women: from a grandmother launching a pickle jar against a drone to volunteers with territorial defense units. However, comparable stories have been entirely lacking on Russia’s side: How come? Here is another piece: the stories of rape and abuse in Russian-occupied Ukrainian territories have shaken the world, with male Russian soldiers featured as systematic perpetrators of war crimes. Were there any female soldiers or pro-Russian civilians involved? The historical background of multiple conflicts across continents does suggest an active women’s role as perpetrators of war crimes (including rape) and terrorism, not only victims. Perhaps it is only a matter of time until stories of Russian women involved in these crimes start to emerge. How do these pieces fit together? I delve into these narratives in an information environment that is still extremely limited (particularly in terms of Russian-language sources).

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After decades of discourse on disarmament and non-proliferation, the war in Ukraine has effectively marked the return of nuclear weapons to both mainstream public rhetoric and military-policy planning, and highlighted the growing importance of strategic deterrence. Russia’s progressively more intense nuclear saber-rattling over the past decade is partly due to an updated NATO posture and gradual commitments by Western nuclear powers to update their arsenals. While Western analysts have consistently reported seeing few substantive changes on the ground to accompany Russian verbiage, the escalatory pattern is frequently compared to the Cuban missile crisis at the height of the Cold War. In contrast, the Eastern European Baltic states, typically at the forefront of Russia’s containment agenda, consider Russia’s nuclear rhetoric with seemingly little concern, discounting the threats as empty. A regularly under-appreciated product of differing Cold War experiences, the gap between these divergent transatlantic perspectives has barely changed despite substantial changes to the geopolitical situation against which the nuclear rhetoric has sounded.

This paper traces and compares the transatlantic perceptions of Russia’s nuclear rhetoric from the start of the conflict in Ukraine in 2014 to the latest round of escalatory threats issued in early 2023. It is based on a review of open-source literature, public opinion polls, and interviews with security experts previously conducted by the author. The paper starts with an outline of transatlantic positions based on previous research and proceeds to present a detailed narrative comparison in the context of Russia’s conventional war in Ukraine that started in February 2022.

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