There exists a core dual principle of the modern world order that aggressive attack is prohibited in international relations and that necessary and proportional force may be used in response to such an attack. This dual principle is embodied in Articles of the United Nations Charter and in virtually every modern normative statement about the use of force in international relations. Indeed, together there two principles are the most important doctrine to emerge in more than 2000 years of human thought regarding the prevention of war. In our contemporary world of conflicting ideology and nuclear threat, no task in more important for statesmen than maintaining that integrity of this principle in both its critical and reciprocal dimensions: prohibition of aggression and the right defense.
