The Peloponnesian War, being one of the earliest wars with a good historical record, sets an important precedent for those interested in international relations. The information related by Thucydides in his writings on the war allows comparisons to be drawn with modern wars and conclusions to be drawn. One of the most important of these conclusions that may be drawn is that, like in modern times, the balance of power between states in an anarchic international society, if upset or perceived to have been upset, will bring nations to war. This is evidenced strongly in Thucydides writings on the Peloponnesian War, and while other factors may have led to war, it is unlikely that any of the Greek city-states of Hellas would have gone to war. When one hears of anarchy, immediately thoughts of chaos and disorder enter the mind, but in the international system of anarchy, many events are predictable. To a degree disorder is present, as war is always possible, and nearly always an imminent danger. However, international events such as war may be predicted. In an anarchic system there is an ever-present uncertainty of the future and uncertainty of the intentions of other states. In the Greek world of Thucydides described in his history of the Peloponnesian War, the opposing states ' uncertainty of the others ' intentions led to a security dilemma in which Sparta was forced to increase its security to match the seemingly increasing security of Athens. The building of Athens ' long walls protecting its naval power and its interference in Corcyra were important events in beginning the war, primarily because of the dramatic increase in Athenian power these events represented to the Spartans. These actions put Athens in a strong position to increase its power steadily in the coming years, also steadily decreasing Spartan power forcing Sparta into a situation in which it must increase its own security in order to
Cited: Nye, Jr., Joseph S. Understanding International Conflicts. 5th ed. 2005. 1-20. Thucydides. History of the Peloponnesian War.