Polarity in

international relations International relations (IR), sometimes referred to as international studies and international affairs, is the scientific study of interactions between sovereign states. In a broader sense, it concerns all activities between states—such a ...

is any of the various ways in which

power Power most often refers to: * Power (physics), meaning "rate of doing work" ** Engine power, the power put out by an engine ** Electric power * Power (social and political), the ability to influence people or events ** Abusive power Power may a ...

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. Scholars differ as to whether bipolarity or unipolarity is likely to produce the most stable and peaceful outcomes.

Kenneth Waltz Kenneth Neal Waltz (; June 8, 1924 – May 12, 2013) was an American political scientist who was a member of the faculty at both the University of California, Berkeley and Columbia University and one of the most prominent scholars in the field of ...

and

John Mearsheimer John Joseph Mearsheimer (; born December 14, 1947) is an American political scientist and international relations scholar, who belongs to the realist school of thought. He is the R. Wendell Harrison Distinguished Service Professor at the Univers ...

are among those who argue that bipolarity tends to generate relatively more stability, whereas John Ikenberry and

William Wohlforth William Curti Wohlforth (born 1959) is the Daniel Webster Professor of Government in the Dartmouth College Department of Government, of which he was chair for three academic years (2006-2009). Wohlforth was Editor-in-chief of ''Security Studies ...

are among those arguing for the stabilizing impact of unipolarity. Some scholars, such as

Karl Deutsch Karl Wolfgang Deutsch (21 July 1912 – 1 November 1992) was a social and political scientist from Prague. He was a professor at MIT, Yale University and Harvard University, as well as Director of Wissenschaftszentrum Berlin (International Insti ...

and J. David Singer, argued that multipolarity was the most stable structure.

Unipolarity

Unipolarity is a condition in which one state under the condition of international anarchy enjoys a preponderance of power and faces no competitor states. A unipolar state is not the same as an

empire An empire is a "political unit" made up of several territories and peoples, "usually created by conquest, and divided between a dominant center and subordinate peripheries". The center of the empire (sometimes referred to as the metropole) ex ...

or a hegemon that can control the behavior of all other states. Scholars have debated the durability and peacefulness of unipolarity.

argues that unipolarity is durable and peaceful because it reduces the likelihood of hegemonic rivalry (because no state is powerful enough to challenge the unipole) and it reduces the salience and stakes of balance of power politics among the major states, thus reducing the likelihood that attempts at balances of power cause major war. Wohlforth builds his argument on

hegemonic stability theory Hegemonic stability theory (HST) is a theory of international relations, rooted in research from the fields of political science, economics, and history. HST indicates that the international system is more likely to remain stable when a single sta ...

and a rejection of the balance of power theory. With no great power to check its adventurism, the United States will weaken itself by misusing its power internationally. “Wide latitude” of “policy choices” will allow the U.S. to act capriciously on the basis of “internal political pressure and national ambition.” According to

Carla Norrlöf Carla Norrlöf is a Swedish-Ethiopian political scientist. She is Associate Professor of Political Science at the University of Toronto. Her research focuses on hegemony, as well as the international political economy of trade, investment and secur ...

, U.S. unipolarity is stable and sustainable due to a combination of three factors: 1. The status of the American dollar as the world's dominant reserve currency, 2. American commercial power, and 3. American military preponderance. The United States benefits disproportionately from its status as hegemon. Other states do not challenge U.S. hegemony because many of them benefit from the U.S.-led order, and there are significant coordination problems in creating an alternative world order. Nuno P. Monteiro argues that unipolarity is conflict-prone, both between the unipole and other states, and exclusively among other states. Monteiro substantiates this by remarking that “the United States has been at war for thirteen of the twenty-two years since the end of the Cold War. Put another way, the first two decades of unipolarity, which make up less than 10 percent of U.S. history, account for more than 25 percent of the nation’s total time at war.” Kenneth Waltz that unipolarity is “the least durable of international configurations.” Secondly, even if the United States acts benevolently, states will still attempt to balance against it because the power asymmetry demands it: In a self-help system, states do not worry about other states’ intentions as they do other states' capabilities. “Unbalanced power leaves weaker states feeling uneasy and gives them reason to strengthen their positions,” Waltz says. In a 2009 study,

Martha Finnemore Martha Finnemore (born 1959) is an American constructivist scholar of international relations, and University Professor at the Elliott School of International Affairs at George Washington University. She is considered among the most influential int ...

argues that unipolarity has, contrary to some expectations, not given the United States a free rein to do what it wants and that unipolarity has proven to be quite frustrating for the United States. The reasons for this is that unipolarity does not just entail a material superiority by the unipole, but also a social structure whereby the unipole maintains its status through legitimation, and institutionalization. In trying to obtain legitimacy from the other actors in the international system, the unipole necessarily gives those actors a degree of power. The unipole also obtains legitimacy and wards off challenges to its power through the creation of institutions, but these institutions also entail a diffusion of power away from the unipole. In a 2021 study, Yuan-kang Wang argues from the experience of Ming China (1368–1644) and Qing China (1644–1912) that the durability of unipolarity is contingent on the ability of the unipole to sustain its power advantage and for potential challengers to increase their power without provoking a military reaction from the unipole.

American primacy

Numerous thinkers predicted U.S primacy in the 20th century onwards, including William Gladstone,

Michel Chevalier Michel Chevalier (; 13 January 1806 – 18 November 1879) was a French engineer, statesman, economist and free market liberal. Biography Born in Limoges, Haute-Vienne, Chevalier studied at the ''École Polytechnique'', obtaining an engineerin ...

K'ang Yu-wei Kang Youwei (; Cantonese: ''Hōng Yáuh-wàih''; 19March 185831March 1927) was a prominent political thinker and reformer in China of the late Qing dynasty. His increasing closeness to and influence over the young Guangxu Emperor spar ...

, (1885): ''The One World Philosophy'', (tr. Thompson, Lawrence G., London, 1958, pp. 79-85).

Georges Vacher de Lapouge Count Georges Vacher de Lapouge (; 12 December 1854 – 20 February 1936) was a French anthropologist and a theoretician of eugenics and racialism. He is known as the founder of anthroposociology, the anthropological and sociological study of race ...

, ''L`Aryen: Son Role Social'', (Nantes, 1899: chapter "L`Avenir des Aryens," pp. XXXI-XXXII).

H. G. Wells Herbert George Wells"Wells, H. G."
Revised 18 May 2015. ''

Anticipations ''Anticipations of the Reaction of Mechanical and Scientific Progress upon Human Life and Thought'', generally known as ''Anticipations'', was written by H.G. Wells at the age of 34. He later called the book, which became a bestseller, "the keys ...

'' (1900), and

William Thomas Stead William Thomas Stead (5 July 184915 April 1912) was a British newspaper editor who, as a pioneer of investigative journalism, became a controversial figure of the Victorian era. Stead published a series of hugely influential campaigns whilst e ...

. Liberal institutionalist

John Ikenberry Gilford John Ikenberry (October 5, 1954) is a theorist of international relations and United States foreign policy, and the Albert G. Milbank Professor of Politics and International Affairs at Princeton University. He is known for his work on li ...

argues in a series of influential writings that the United States purposely set up an international order after the end of World War that sustained US primacy. In his view, realist predictions of power balancing did not bear fruit because the United States engaged in strategic restraint after World War II, thereby convincing weaker states that it was more interested in cooperation rather than domination. U.S. strategic restraint allowed weaker countries to participate in the make-up of the post-war world order, which limited opportunities for the United States to exploit total power advantages. Ikenberry notes that while the United States could have unilaterally engaged in unfettered power projection, it decided instead to “lock in” its advantage long after zenith by establishing an enduring institutional order, gave weaker countries a voice, reduced great power uncertainty, and mitigated the

security dilemma In 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 k ...

. The liberal basis of U.S. hegemony—a transparent democratic political system—has made it easier for other countries to accept the post-war order, Ikenberry explains. “American hegemony is reluctant, open, and highly institutionalized—or in a word, liberal” and “short of large-scale war or a global economic crisis, the American hegemonic order appears to be immune to would-be hegemonic challengers.” Michael Beckley argues American primacy is vastly underestimated because power indices frequently fail to take into account GDP per capita in the U.S. relative to other purportedly powerful states, such as China and India. In 2011, Barrry Posen argued that unipolarity was in wane and that the world was shifting towards multipolarity. In 2019, John Mearsheimer argued that the international system was shifting from unipolarity to multipolarity. In 2022, William Wohlforth argued that the international system was heading towards a system that can be characterized neither as bipolarity nor multipolarity. He added that polarity did not appear to matter as much in the current international system, as great powers command a far smaller share of power vis-a-vis the rest of the states in the international system.

Bipolarity

Bipolarity is a distribution of power in which two states have a preponderance of power. In bipolarity, spheres of influence and alliance systems have frequently developed around each pole. For example, in the Cold War of 1947-1991, most Western and capitalist states would fall under the influence of the US, while most Communist states would fall under the influence of the

USSR The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen nationa ...

. Kenneth Waltz's influential ''

Theory of International Politics ''Theory of International Politics'' is a 1979 book on international relations theory by Kenneth Waltz that creates a structural realist theory, neorealism, to explain international relations. Taking into account the influence of neoclassical e ...

'' argued that bipolarity tended towards the greatest stability because the two great powers would engage in rapid mutual adjustment, which would prevent inadvertent escalation and reduce the chance of power asymmetries forming. Dale Copeland has challenged Waltz on this, arguing that bipolarity creates a risk for war when a power asymmetry or divergence happens. Historic examples of bipolarity include

Great Britain Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of , it is the largest of the British Isles, the largest European island and the ninth-largest island in the world. It i ...

and

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan area ...

in 18th century from the end of the

War of the Spanish Succession The War of the Spanish Succession was a European great power conflict that took place from 1701 to 1714. The death of childless Charles II of Spain in November 1700 led to a struggle for control of the Spanish Empire between his heirs, Phil ...

(1701-1715) until the

Seven Years' War The Seven Years' War (1756–1763) was a global conflict that involved most of the European Great Powers, and was fought primarily in Europe, the Americas, and Asia-Pacific. Other concurrent conflicts include the French and Indian War (175 ...

(1754-1763), and the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

and the

Soviet Union The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, ...

during the Cold War (1947-1991). According to Sullivan and Donnelly, a "polycentric" period emerged between 1963 and 1988 - in contrast to the bipolar period of 1945 to 1962. De Tocqueville foreshadowed in 1830 a great-power bipolarity similar to that of the Cold War.

Multipolarity

Multipolarity is a distribution of power in which more than two nation-states have nearly equal amounts of power. The

Concert of Europe The Concert of Europe was a general consensus among the Great Powers of 19th-century Europe to maintain the European balance of power, political boundaries, and spheres of influence. Never a perfect unity and subject to disputes and jockeying ...

, a period from after the

Napoleonic Wars The Napoleonic Wars (1803–1815) were a series of major global conflicts pitting the French Empire and its allies, led by Napoleon I, against a fluctuating array of European states formed into various coalitions. It produced a period of Fren ...

to the

Crimean War The Crimean War, , was fought from October 1853 to February 1856 between Russia and an ultimately victorious alliance of the Ottoman Empire, France, the United Kingdom and Piedmont-Sardinia. Geopolitical causes of the war included the ...

, was an example of peaceful multipolarity (the great powers of Europe assembled regularly to discuss international and domestic issues), as was the Interwar period. Examples of wartime multipolarity include

World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...

, the

Thirty Years War The Thirty Years' War was one of the longest and most destructive conflicts in European history, lasting from 1618 to 1648. Fought primarily in Central Europe, an estimated 4.5 to 8 million soldiers and civilians died as a result of battl ...

, the

Warring States period The Warring States period () was an era in ancient Chinese history characterized by warfare, as well as bureaucratic and military reforms and consolidation. It followed the Spring and Autumn period and concluded with the Qin wars of conquest ...

, the

Three Kingdoms The Three Kingdoms () from 220 to 280 AD was the tripartite division of China among the dynastic states of Cao Wei, Shu Han, and Eastern Wu. The Three Kingdoms period was preceded by the Eastern Han dynasty and was followed by the West ...

period and the tripartite division between

Song dynasty The Song dynasty (; ; 960–1279) was an imperial dynasty of China that began in 960 and lasted until 1279. The dynasty was founded by Emperor Taizu of Song following his usurpation of the throne of the Later Zhou. The Song conquered the rest ...

Liao dynasty The Liao dynasty (; Khitan language, Khitan: ''Mos Jælud''; ), also known as the Khitan Empire (Khitan: ''Mos diau-d kitai huldʒi gur''), officially the Great Liao (), was an Dynasties in Chinese history, imperial dynasty of China that exi ...

/ Jin dynasty/

Yuan dynasty The Yuan dynasty (), officially the Great Yuan (; xng, , , literally "Great Yuan State"), was a Mongol-led imperial dynasty of China and a successor state to the Mongol Empire after its division. It was established by Kublai, the fift ...

World empires and colonies around World War I

Classical realist theorists, such as

Hans Morgenthau Hans Joachim Morgenthau (February 17, 1904 – July 19, 1980) was a German-American jurist and political scientist who was one of the major 20th-century figures in the study of international relations. Morgenthau's works belong to the tradition o ...

and

E. H. Carr Edward Hallett Carr (28 June 1892 – 3 November 1982) was a British historian, diplomat, journalist and international relations theorist, and an opponent of empiricism within historiography. Carr was best known for '' A History of Soviet Rus ...

, hold that multipolar systems are more stable than bipolar systems, as great powers can gain power through alliances and petty wars that do not directly challenge other powers; in bipolar systems, classical realists argue, this is not possible. Neorealist hold that multipolar systems are particularly unstable and conflict-prone, as there is greater complexity in managing alliance systems, and a greater chance of misjudging the intentions of other states. Thomas Christensen and Jack Snyder argue that multipolarity tends towards instability and conflict escalation due to "chain-ganging" (allies get drawn into unwise wars provoked by alliance partners) and "buck-passing" (states which do not experience an immediate proximate threat do not balance against the threatening power in the hope that others carry the cost of balancing against the threat). Multipolarity does not guarantee

multilateralism In international relations, multilateralism refers to an alliance of multiple countries pursuing a common goal. Definitions Multilateralism, in the form of membership in international institutions, serves to bind powerful nations, discourage ...

and can pose a challenge against multilateralism. According to

Kemal Derviş Kemal Derviş (; born 10 January 1949) is a Turkish economist and politician, and former head of the United Nations Development Programme. He was honored by the government of Japan for having "contributed to mainstreaming Japan's development ass ...

, a decline in unipolarity creates a crisis in multilateralism; it is possible to revive multilateralism in a multipolar system, but this is more threatened and the structure to do so is not fully developed. In multipolarity, larger powers can negotiate "mega-regional" agreements more easily than smaller ones. When there are multiple competing great powers, this can lead to the smaller states being left out of such agreements. Though multipolar orders form regional hegemonies around 'poles' or great powers, this can weaken economic interdependencies within regions, at least in regions without a great power. Additionally, as multipolar systems can tend to regional hegemonies or bounded orders, agreements are formed within these bounded orders rather than globally. Though, Mearsheimer predicts the persistence of a thin international order within multipolarity, which constitutes some multilateral agreements.

Measuring the power concentration

The

Correlates of War The Correlates of War project is an academic study of the history of warfare. It was started in 1963 at the University of Michigan by political scientist J. David Singer. Concerned with collecting data about the history of wars and conflict among ...

uses a systemic concentration of power formula to calculate the polarity of a given

great power A great power is a sovereign state that is recognized as having the ability and expertise to exert its influence on a global scale. Great powers characteristically possess military and economic strength, as well as diplomatic and soft power in ...

system. The formula was developed by J. David Singer et al. in 1972. :

\text_t = \sqrt

:''t'' = the time at which the concentration of resources (i.e. power) is being calculated :''i'' = the state of which the proportion of control over the system's power is being measured :''N''_''t'' = the number of states in the great power system at time ''t'' :''S'' = the proportion of power possessed. Hence, ''S''_''it'' = the proportion of power possessed by state ''i'' at time ''t''. The expression

\sum_^n (S_)^2

represents the sum of the squares of the proportion of power possessed by all states in the great power system. The closer the resulting concentration is to zero, the more evenly divided power is. The closer to 1, the more concentrated power is. There is a general but not strict correlation between concentration and polarity. It is rare to find a result over 0.5, but a result between 0.4 and 0.5 usually indicates a unipolar system, while a result between 0.2 and 0.4 usually indicated a bipolar or multipolar system. Concentration can be plotted over time, so that the fluctuations and trends in concentration can be observed.

Bibliography

* Thompson, William R. ''On Global War: Historical–Structural Approaches to World Politics.'' Columbia, SC: University of South Carolina Press, 1988, pp. 209–210.

Notes

References

External links

Global Power Barometer
{{DEFAULTSORT:Polarity In International Relations International relations theory

Unipolarity

American primacy

Bipolarity

Multipolarity

Measuring the power concentration

See also

Bibliography

Notes

References

External links