Balance of power (international relations)The balance of power theory in international relations suggests that states may secure their survival by preventing any one state from gaining enough military power to dominate all others. If one state becomes much stronger, the theory predicts it will take advantage of its weaker neighbors, thereby driving them to unite in a defensive coalition. Some realists maintain that a balance-of-power system is more stable than one with a dominant state, as aggression is unprofitable when there is equilibrium of power between rival coalitions.
Realism (international relations)Realism is one of the dominant schools of thought in international relations theory, theoretically formalizing the Realpolitik statesmanship of early modern Europe. Although a highly diverse body of thought, it is unified by the belief that world politics is always and necessarily a field of conflict among actors pursuing wealth and power. The theories of realism are contrasted by the cooperative ideals of liberalism in international relations. Realists are divided into three classes based on their view of the essential causes of interstate conflict.
Polarity (international relations)Polarity in international relations is any of the various ways in which power is distributed within the international system. It describes the nature of the international system at any given period of time. One generally distinguishes three types of systems: unipolarity, bipolarity, and multipolarity for three or more centers of power. The type of system is completely dependent on the distribution of power and influence of states in a region or globally.
Neorealism (international relations)Neorealism or structural realism is a theory of international relations that emphasizes the role of power politics in international relations, sees competition and conflict as enduring features and sees limited potential for cooperation. The anarchic state of the international system means that states cannot be certain of other states' intentions and their security, thus prompting them to engage in power politics. It was first outlined by Kenneth Waltz in his 1979 book Theory of International Politics.
Security dilemmaIn international relations, the security dilemma (also referred to as the spiral model) is when the increase in one state's security (such as increasing its military strength) leads other states to fear for their own security (because they do not know if the security-increasing state intends to use its growing military for offensive purposes). Consequently, security-increasing measures can lead to tensions, escalation or conflict with one or more other parties, producing an outcome which no party truly desires; a political instance of the prisoner's dilemma.
International relations theoryInternational relations theory is the study of international relations (IR) from a theoretical perspective. It seeks to explain behaviors and outcomes in international politics. The four most prominent schools of thought are realism, liberalism, constructivism, and rational choice. Whereas realism and liberalism make broad and specific predictions about international relations, constructivism and rational choice are methodological approaches that focus on certain types of social explanation for phenomena.
Democratic peace theoryProponents of "democratic peace theory" argue that both liberal and republican forms of democracy are hesitant to engage in armed conflict with other identified democracies. Different advocates of this theory suggest that several factors are responsible for motivating peace between democratic states. Individual theorists maintain "monadic" forms of this theory (democracies are in general more peaceful in their international relations); "dyadic" forms of this theory (democracies do not go to war with other democracies); and "systemic" forms of this theory (more democratic states in the international system makes the international system more peaceful).
Power politicsPower politics is a theory of power in international relations which contends that distributions of power and national interests, or changes to those distributions, are fundamental causes of war and of system stability. The concept of power politics provides a way of understanding systems of international relations: in this view, states compete for the world's limited resources, and it is to an individual state's advantage to be manifestly able to harm others.
Pax AmericanaPax Americana (Latin for "American Peace", modeled after Pax Romana and Pax Britannica; also called the Long Peace) is a term applied to the concept of relative peace in the Western Hemisphere and later in the world after the end of World War II in 1945, when the United States became the world's dominant economic, cultural, and military power. In this sense, Pax Americana has come to describe the military and economic position of the United States relative to other nations. The U.S.
Anarchy (international relations)In international relations theory, the concept of anarchy is the idea that the world lacks any supreme authority or sovereignty. In an anarchic state, there is no hierarchically superior, coercive power that can resolve disputes, enforce law, or order the system of international politics. In international relations, anarchy is widely accepted as the starting point for international relations theory.
