THE THREAT AND USE of force in the twenty-first century is likely to be characterised by some features that are enduring and by others that are unique to this particular stage of world history. Force will continue to be wielded by some states to further their political objectives, and for many it will constitute an important tool in their efforts to shape the strategic environment, deter armed attack, and change adversary behaviour.

As a component of grand strategy, the threat and use of force has always been viewed as an important shaping mechanism. States have used force to induce others to submit to their rule, to cooperate, and to abstain from particular actions or modes of behaviour. They have used it to extend their influence and access to resources and labour, to impose their preferred ideologies or models of governance, to deter rivals, and to punish infractions of international law or local agreements. Military force is also used to gain respect, instil caution, and ensure that diplomatic pressure is credible.

The defence strategies of states will continue to incorporate elements of deterrence and response as they seek to dissuade real or potential military adversaries from contemplating aggression, and try to retain the ability to prevail should deterrence fail. Plainly nuclear deterrence still has an important role to play at the level of inter-state competition.