Epistemic Intermediaries and Europe's Defence Turn: Expert Knowledge and the Communication of the CSDP

Amid escalating geopolitical instability and institutional recalibration, the European Union’s Common Security and Defence Policy (CSDP) has entered a critical phase of communicative and strategic transformation. This article investigates how expert knowledge about the CSDP is framed and disseminated through European public institutional communication, with particular attention to the role of epistemic intermediaries -understood as scholars, policy advisors, military personnel, and civil servants- who mediate between institutional narratives and public understanding. Based on a cross-national survey of 129 experts, the study examines their perceptions of communication effectiveness, knowledge accessibility, and the legitimacy of the CSDP. Findings point to a fragmented landscape shaped by institutional opacity, cognitive asymmetries, and technocratic framing. While experts broadly support deeper defence integration, they express skepticism toward current EU communication strategies, especially regarding sufficiency, clarity, and citizen engagement. The article argues that in high-stakes policy domains like defence, communicative legitimacy is a core dimension of strategic autonomy. It concludes by emphasizing the centrality of epistemic intermediaries in shaping the diffusion, reception, and contestation of European security narratives, and calls for more transparent, dialogic, and epistemically plural communication infrastructures.