This high-level conference will consider the options and implications of Brexit, from the perspectives of the United Kingdom, the rest of Europe and the rest of the world. Please see programme for more information.

I consider a model in which two states choose how much to arm and whether to attack in successive periods. Arms are useful not only for deterrence or taking territory, but also because they influence the resolution of a set of disputed issues. It is shown that states can cooperate on the issues by limiting military competition, but only as far as a “war constraint” allows. Factors determining the tightness of the war constraint imply hypotheses about the international determinants of military eort and thus the costs of anarchy.