 How states relate to one another? Since the territorial area of the earth is divided among different states, interstate relations must occupy much of a state's time and energy. The natural tendency of a state is to expand its power, and externally such expansion takes place by conquest of a territorial area. Unless a territory is stateless or uninhabited, any such expansion involves an inherent conflict of interest between one set of state rulers and another. Only one set of rulers can obtain a monopoly of coercion over any given territorial area at any one time. Complete power over a territory by state X can only be obtained by the expulsion of state Y. War, while risky, will be an ever-present tendency of states, punctuated by periods of peace, and by shifting alliances and coalitions between states. We have seen that the internal or domestic attempt to limit the state, in the 17th through 19th centuries, reached its most notable form in constitutionalism. Its external or foreign affairs counterpart was the development of international law, especially such forms as the laws of war and neutral's rights. Laws of international law were originally purely private, growing out of the need of merchants and traders everywhere to protect their property and adjudicate disputes. Examples are Admiralty Law and the Law Merchant. But even the government rules emerged voluntarily and were not imposed by any international super-state. The object of the laws of war was to limit inter-state destruction to the state apparatus itself, thereby preserving the innocent civilian public from the slaughter and devastation of war. The object of the development of neutral's rights was to preserve private civilian international commerce, even with enemy countries, from seizure by one of the warring parties. The overriding aim, then, was to limit the extent of any war, and particularly to limit its destructive impact on the private citizens of the neutral and even the warring countries. The jurist F. J. P. Veal charmingly described such civilized warfare as it briefly flourished in 15th century Italy. The rich burgers and merchants of medieval Italy were too busy making money and enjoying life to undertake the hardships and dangers of soldering themselves, so they adopted the practice of hiring mercenaries to do their fighting for them, and being thrifty, business-like folk, they dismissed their mercenaries immediately after their services could be dispensed with. Wars were, therefore, fought by armies hired for each campaign. For the first time, soldering became a reasonable and comparatively harmless profession. The generals of that period manoeuvred against each other, often with consummate skill, but when one had won the advantage, his opponent generally either retreated or surrendered. It was a recognized rule that a town could only be sacked if it offered resistance. Immunity could always be purchased by paying a ransom. As one natural consequence, no town ever resisted, it being obvious that a government too weak to defend its citizens had forfeited their allegiance. Civilians had little to fear from the dangers of war, which were the concern only of professional soldiers. The well-nigh-absolute separation of the private civilian from the state's wars in eighteenth-century Europe is highlighted by Neff. Even postal communications were not successfully restricted for long in wartime. Letters circulated without censorship, with the freedom that astonishes the twentieth-century mind. The subjects of two warring nations talked to each other if they met, and when they could not meet, corresponded, not as enemies, but as friends. The modern notion hardly existed that subjects of any enemy country are partly accountable for the belligerent acts of their rulers, nor had the warring rulers any firm disposition to stop the communications with subjects of the enemy. The old inquisitorial practices of espionage in connection with religious worship and belief were disappearing, and no comparable inquisition in connection with political or economic communications was even contemplated. States were originally created to provide safe conduct in time of war. During most of the eighteenth-century, it seldom occurred to Europeans to abandon their travels in a foreign country, which their own was fighting. And trade, being increasingly recognised as beneficial to both parties, eighteenth-century warfare also counterbalances a considerable amount of trading with the enemy. How far states have transcended rules of civilised warfare in this century needs no elaboration here. In the modern era of total war, combined with the technology of total destruction, the very idea of keeping war limited to the state apparatus seems even more quaint and obsolete than the original constitution of the United States. When states are not at war, agreements are often necessary to keep frictions at a minimum. One doctrine that has gained curiously wide acceptance is the alleged sanctity of treaties. This concept is treated as the counterpart of the sanctity of contract. But a treaty and a genuine contract have nothing in common. A contract transfers, in a precise manner, titles to private property. Since the government does not in any proper sense own its territorial area, any agreements that it concludes do not confer titles to property. If, for example, Mr Jones sells or gives his land to Mr Smith, Jones's air cannot legitimately descend upon Smith's air and claim the land as rightfully his. The property title has already been transferred. Old Jones' contract is automatically binding upon Young Jones, because the former had already transferred the property. Young Jones therefore has no property claim. Young Jones can only claim that which he has inherited from Old Jones, and Old Jones can only bequeath property which he still owns. But if, at a certain date, the government of, say, Ruritania is coerced or even bribed by the government of Aldavia into giving up some of its territory, it is absurd to claim that the governments or inhabitants of the two countries are forever barred from a claim to reunification of Ruritania on the grounds of the sanctity of a treaty. Neither the people nor the land of North West Ruritania are owned by either of the two governments. As a corollary, one government can certainly not bind, by the dead hand of the past, a later government through treaty. A revolutionary government which overthrew the king of Ruritania could similarly hardly be called to account for the king's actions or debts, for a government is not, as is a child, a true heir to its predecessor's property.