barty, you are getting trounced. quite embaressing. vimothy, i dunno, you only speak in gnomic non sequiturs so i dont know how to judge your performance.
If aggression between states is to be outlawed and punished (for example by hanging those responsible), then obviously there must an authority capable of issuing laws encompassing that, determining whether states are guilty of transgressing the law, and punishing those who do so. That authority cannot possibly exist on a purely consensual basis - which is why the international system has historically been (basically) anarchy and international law was described as "the vanishing point of jurisprudence".