We need to understand why war is such a recurring event in the history of nation-states and also the nature of international affairs and the determining factors that cause action, reaction, cooperation, hostility and peace between states in the international system. War has always been a conflict between countries through the use of weapons. When nations decide to go to war against each other, millions of money are spent, and not only are money and materials wasted, but they also cost hundreds or even millions of lives. So, in most cases, not only soldiers die, but innocent people also lose their lives. Killing people for any reason, such as power, race, etc., and then because nations don't think that way and don't have the same worldview, is not right. This is why peace is the contrast to war. Peace is mostly described as a quality that operates harmoniously and keeps a society or relationship safe. This means that hostility does not exist, because the security of nation-states and their international relations on social and economic issues are important, and equality and good justice are trusted. Bill Newman in his article “A Brief Introduction to Theories of International Political Relations and Foreign Policy” states that classical realism is a state theory that holds that all states seek power and that states seek to increase their own power; they want to diminish the power of their enemies; and everything they do is in the name of accumulating power. States see other powerful states as rivals because power, when it is not in your hands, is threatening. (Newman Poli 468) This means that states want the power to dominate other states because they think that having… paper… Furthermore, the rules did not prevent the United States from reaching Afghanistan and Iraq and constructivism does not fully explain the peace because most of his explanations concern humanitarian intervention. Humanitarian aid does not bring peace. Why didn't the United States or Europe intervene in the Rwandan genocide? We all know this is so because the Americans had no interests, a small African country with no minerals and most of the UN peacekeepers were removed from Rwanda. Constructivism is only critical where other theories have failed to provide the adequate explanation and makes no predictions, and also according to Wendt himself who identifies constructivism as a tool of analysis, rather than a tool of predictions. Wendt (1992). Finally, constructivists forget that individual experiences and attitudes vary between actors and that based on the “what?” but not on the “Why?” and the “How?”.