“…The issue is a classic ontological one. It has been discussed explicitly and implicitly across a range of literature, including intelligence failures (Bar-Joseph and Levy, 2009; Dahl, 2005; Gentry, 2008; Rousseau, 2006), foreign policy decision making (Astorino-Courtois, 2000; Vertzberger, 1990), stress and behaviour (Janis and Mann, 1977; Post, 2004), crisis management (Boin et al , 2005; Robb, 2007) and risk management (Bostrom and Ćirković, 2008; Bracken et al , 2008; Eriksson, 2001). We focus here briefly on debates within international relations (IR) theory, partly because they deal with cross-national warning signs but also to illustrate broader points about the lack of a universally agreed ‘hard science’ of warning signs.…”