This paper evaluates strategies to combat terrorism under the premise that violent radicalization operates as a social contagion. We tested antiterrorism, counterterrorism, and counter radicalization strategies in isolation and combination. All policies were tested in a simulation model built to the DIME-PMESII military standard across 10 years under optimal, realistic, and worst-case scenarios. Tested policies include established and novel approaches. The two novel approaches focused deterrence and terror contagion containment performed better. First focused deterrence reduced terror incidents by 68% under optimal conditions. However, this effect was reduced in half if it provoked a backlash. The terror contagion containment strategy borrows from well-studied methods on limiting social contagions following celebrity suicide, known as the Werther effect. As a counter radicalization strategy, it reduced incidents by 98% even with a realistic constraint of variable public support. But under a stress-test of a worst-case scenario, terror contagion containment struggled to reduce violence. However, when bolstered by adding focused deterrence and grievance reduction, the combination reduced incidents by 67% in the worst-case scenario. These results point to promising avenues for combating terrorism through further research of novel approaches followed by the development of pilot programs
