Protean Jus Ad Bellum

The jus ad bellum is generally viewed as a static field of law. The standard account is that when the UN Charter was adopted in 1945, it enshrined a complete prohibition on the use of force in inter-state relations, except when action is being taken in self-defense against an armed attack or under authorization of the UN Security Council. Yet it seems likely that in the years to come, many states and non-state actors will increasingly insist upon a different vision of the jus ad bellum, one that conceives of it as more protean in nature. Protean jus ad bellum acknowledges that, as of 1945, the static view was correct, but that over time-as we approach the 70th anniversary of the United Nations-the jus ad bellum is changing, buffeted in particular by several significant developments: (1) the emergence of weapons of mass destruction of various types potentially controllable by states and non-state actors; (2) the rise of global terrorism as a mechanism for projecting violence against states by non-state actors; (3) the elevation of the person to a central place in the realm of international law, both in terms of being protected and in terms of being accountable for misconduct; (4) the inability of the Security Council to be accepted by all states as a disinterested arbiter willing and capable of acting to address all threats to international peace and security as they arise; and (5) the continuing erosion of the sanctity of the sovereign state, resulting from exposure to myriad effects of globalization, including intrusive transnational rule of law programs, election monitoring, incessant and extensive media coverage, powerful transnational corporations and non-governmental organization, and relatively unrestricted transborder movement of capital, goods, and persons across borders.This essay suggests that the failure to either formally accept or reject the idea of protean jus ad bellum is likely, over time, to diminish the jus ad bellum's effectiveness as a normative regime. Too often transnational uses of military force are occurring in circumstances that are inconsistent with the idea of a static jus ad bellum: states and non-state actors are, at least in some situations, tolerating certain types of force in response to the overarching developments noted above. As the International Criminal Court moves closer to including aggression within its mandate for indicting and prosecuting persons, government leaders may see greater value in clarifying what uses of force are permissible. Things could continue as they are. But in the long-term, if the jus ad bellum is not to break down, then a more formal way should be found either to reject the notion of protean jus ad bellum or to accept it, and if the latter, then to try to identify the contemporary rules in this area, either through formal amendment of the UN Charter, through authoritative interpretations by the principal organs of the United Nations or regional organizations, or through other means.