From a realist perspective, decisions by governments (or “states”) to go to war are the product of all states’ involuntary participation in eternal quests for power and security due to an international political environment in which each state fears the actual or potential hostility of other states. Leaders rationally calculate war’s costs and benefits in terms of their state’s power and security (Lieberfeld, 2005).
Therefore, realism sees the states work in an anarchical system, meaning in the absence of higher, trans-governmental and universally recognizable authority no rules are applied in the international realm. The state exists as a full sovereign of its people and territory, and which enjoys the ultimate power of being completely self-determined. By taking into account Waltz’s structure of the international system, there are three elements that define it; its “ordering principle,” “the character of the units” that compose it, and “the distribution of capabilities” between these units. For the neorealist two of these elements never change. Neorealism considers the international system to be permanently anarchic because of the absence of a superior authority, and believes that all the units, or states, are “functionally alike” (Elman in Williams, 2008: 18). The other assumption is that politics is driven by law of human behavior- the mix of urges like the drive for powers, will to dominate, self-interest and ambition. How does all of this help us understand war?