The fractured global threat landscape, split between faith-based extremists and ethno-nationalist groups, produces diverse and incoherent propaganda narratives on social media. Though the incidence of terrorist violence, barring some exceptions in Asia and Africa, has decreased in lethality and frequency, extremist propaganda online, has been mushrooming despite curbs, content moderation and de-platforming by world governments and social media companies. In the digital sphere, terrorist groups have demonstrated adaptability and resilience against an ever-evolving and hostile digital env ...