Two narratives

There are few other principles in international law that have been as fully enshrined by governments as the right to act in self-defence and in accordance with the requirements of national security. Virtually all states assert that their resort to force is justified under the rubric of article 51 of the UN Charter. As any military officer knows, all use of force carries with it a deterrent effect. Force inevitably includes the threat of further force and raises the stakes for future encounters. If deterrence were lawful under all circumstances, it would follow that all use of force – and, for that matter, all threat of it – would be justified under its terms. Obviously no state has argued that the prerogatives of defence are unlimited, and so they are subject to regulation. The question is to what extent.

As shown in chapter 2, there are two rival historical narratives that both appear to make sense in practice. One is the deterrence model, which provides cogent explanations for the fortunate non-occurrence of World War III in the twentieth century and, in a sense, for order and stability. This model also suggests that World War II might have been averted had Hitler been faced with sterner and more timely resistance. The second narrative is the spiral model.