If political statements and media coverage are any guide, it seems Australians today are dying for security. At no other moment in our history has the spectre of war and terrorism so haunted popular, political and scholarly perceptions of Australia's colonial past and of its geopolitical future. And yet, debates over colonial war or genocide and contemporary terrorism have been conducted in more or less complete isolation. In this article I argue that our contemporary obsession with 'security' is premised on the perennial threat of 'insecurity'. This is the problem of in/security, and it has played a central role in the development of Western political thought. More importantly, its formulation in Western political thought provided a powerful justification for the violence of the early decades of Australia's colonisation during which Indigenous Australians could also be said to have been dying for security.