This is a first book-long analysis showing how the notion of 'hybrid warfare' was used to transform security policies and discourses in an EU/NATO country. Building on current debates in International Political Sociology, Critical Security Studies, and Critical Geopolitics, it provides a novel account of how crisis, geopolitics, uncertainty, and expertise are intertwined in the social construction of threats. Based on extensive and original empirical research of large textual archive and elite interviews in the Czech Republic and Brussels, the book shows how officials, bureaucrats,...