Security cannot elude its ambiguous beginnings. Derived from the Latin se (without) and cura (care), the original medieval term suggested not only a freeing of oneself from threat, but also a more negative sense of dangers arising from a hubristic carelessness. Thomas Hobbes framed security in The Leviathan as a universally-coveted, never wholly-attainable value: ‘Nor is it enough for the security, which men desire should last all the time of their life'. Yet his contemporary, Shakespeare, declaimed in Macbeth that ‘Security is Mortals cheefest Enemie'. As a contested concept as well as a political principle, security has relied as much on tropes as it has on troops for its power. What are the implications for the study of security if the basic concept is not only highly contestable, but heavily dependent upon multiple metaphors, differing perspectives, and hierarchies of power to secure their own meanings? How do those meanings shift according to the identity of those who threaten and those who are threatened?  How does an issue become ‘securitized'?  What makes ‘us' safe?