However, going to war is a decision whose seriousness challenges even the most Roget-enriched nuances of the English language. War is not ‘politics carried on by other means’.9 It is a form of organized, pre-meditated mass killing. It can only avoid being mass murder several orders of magnitude above Columbine by being legally justified. It can only avoid moral condemnation and obloquy by being morally justified. Jurisprudence has long contemplated the difference between a group of highway robbers stealing from travellers and a state collecting taxation. The question here is more pressing: what is the difference between a mass murderer and the Commander-in-Chief of a country’s armed forces? Some deny that there is any difference – anarchists mouthing ‘taxation is theft’ in the first case and pacifists insisting that all violence, even in selfdefence, is wrong. The answer to both is legality, legitimacy and morality. The issues of legality take two different forms. First, there are the constitutional and statutory arrangements for conducting war that form part of a country’s domestic law – which may authorize the commencement of war and what procedures must be followed to do so. Second, there is the body of international law on when and how war may be waged (that is, ius ad bellum and ius in bello). These bodies of domestic and international law are related in a variety of ways. In some countries, treaties become a part of domestic law without enabling legislation, so that a war waged contrary to the UN Charter may well be contrary to domestic law. In other countries, the effectiveness of treaties is dependent on the implementation of legislation or on the willingness of courts to use international legal instruments as means for interpreting domestic law.