The strategic communication of terrorist organisations and its influence on public discourse, particularly in the forced migrant context, is an under-researched area. This article argues that terrorist organisations have exploited their marketability in the radicalisation of public discourse. Their (non)discursive strategic communication has influenced public discourse, with impacts on policy and practice. Thirty-two interviews were conducted with civil society organisations and host communities, and complemented by eleven online refugee representations. In addition, the study drew from secondary case reviews of Al Shabaab and a former Islamist. The paper examines and presents key field research findings on the impact of strategic terrorist communication on refugees and host communities. Further, the paper highlights public representations of Islam(ism) and the disruptive character of Islamism brand management. The article additionally explores broader ramifications of terrorist communication on the concept of radicalisation. By examining the synergy between terrorist communication and the speech-acts of other actors, this article contends that besides being a useful concept, radicalisation is a social construct modelled by the perceptions, attitudes, opinions and actions of a coterie of actors. Overall, terrorist communication in rhetoric and action regulates public discourse that in turn inflames a reinforcing feedback loop of reciprocal radicalisation.