This chapter offers a systematic examination of existing scholarly explanations for the emergence and sustenance of terroristic violence through six explanatory frameworks: psychological dimensions, religious dimensions, strategic dynamics, cultural/civilisational contexts, political contexts and economic dimensions. This chapter also sets out the prevailing literature as it relates to the specific stakeholders of terrorism: US mainstream media, ISIS and individual actors/lone wolf. This chapter illustrates how it has been established in the exiting literature that there are numerous causes, impacts and benefits associated with terrorism activism; however, the prevailing literature does not sufficiently or explicitly, systematically or consistently emphasise the inherent duality as it pertains to the related themes associated with the specific explanatory frameworks in relation to terrorism-related activism. The chapter further highlights this as it relates to the specific stakeholders of terrorism—like, for instance, the US mainstream media wide-ranging debates and extensive literature on the US media in relation to terrorism focuses primarily on the media’s symbiotic relationship (between the media and terrorists), framing, packaging, presenting, Orwellian-style coverage, among others, however, it does not explicitly or systematically stress or reinforce the existence of an inherent duality, a multiplicity of negatives and positives simultaneously present in most situations concerning terrorism, in this case, the US mainstream media’s coverage of terrorism. The same for the Islamic State (ISIS/ISIL) and lone wolf/individual actors in which the prevailing literature extensively examines the former emergence, brutal terroristic violence, proficient use of social media, its criminalised war economy, source of revenue, among other things and the latter’s most salient causes, impacts and even the benefits that some lone wolf/individual actors might garner from their engagement in terrorism activism. Howbeit, the literature similar to the existing literature on the US mainstream media in relation to terrorism-activism, does not sufficiently, or explicitly, and neither systematically stresses the existence of an inherent duality as it relates to ISIS’s and lone wolf/individual actors’ engagement in terrorism-activism.KeywordsDefining terrorismPsychologyReligionStrategyCulture/civilisationPoliticsEconomicsISISLone wolfIndividual actorsUS mainstream media