Thucydides, Realism & The Balance of Power



A-Definition of realism

B-The “Melian Dialogue”

C-Thucydides’ political thought

II-Thucydides and the nature of the political system

A-Power and competition

B-Impact on modern scholars

C-Domestic versus interstate relations

D-The Balance of Power

E-Realism and morality

III-Realism in the US Foreign Policy

A-World War I

B-The atomic bomb

C-Intervention in the Third World

1-The Korean War

2-The War in Vietnam


Political realism, as opposed to idealism, is mistakenly sometimes believed to be a theory that flourished during the modern times. Nonetheless, political theory and practice seem to have been as old as human civilization. Thucydides, the Ancient Greek historian of the fifth century BC, is not only the father of scientific history, but also of political “realism,” the school of thought which argues that interstate relations are based on might rather than right. Through his study of the Peloponnesian War, a destructive war which began in 431 BC among Greek city-states, Thucydides observed that the strategic interaction of states followed a discernible and recurrent pattern. According to him, within a given system of states, a certain hierarchy among the states determined the pattern of their relations. Therefore, he claimed that while a change in the hierarchy of weaker states did not ultimately affect a given system, a disturbance in the order of stronger states would decisively upset the stability of the system (Doyle, p. 198). As Thucydides said, the Peloponnesian War was the result of a systematic change, brought about by the increasing power of the Athenian city-state, which tried to exceed the power of the city-state of Sparta. “What made the war inevitable was the growth of Athenian power and the fear which this caused Sparta,” Thucydides wrote in order to illustrate the resulting systematic change; that is, “a change in the hierarchy or control of the international political system” (Doyle, pp. 199-200).

Thucydides’ realism has had a timeless impact on the way contemporary analysts perceive international relations. Adding to the works of Gilpin and Waltz, Leo Strauss of the University of Chicago viewed The Peloponnesian War as containing propositions that could be brought into a coherent framework and identified as “Thucydides’ political philosophy” or serve even as the basis for a series of laws about the science of modern politics (Doyle, p. 201).

In fact, political scientists have treated the work of Thucydides as a coherent attempt to communicate silent universals that have served as the basis for American foreign policy and security doctrine in the post World War II era.

Thus, on one hand, Thucydides was the first to describe international relations as anarchic and immoral. The “Melian dialogue” best exemplifies Thucydides’ view that interstate politics lack regulation and justice. In the “Melian dialogue,” he wrote that, in interstate relations, “the strong do what they have the power to do and the weak accept what they have to accept.” For him, international relations allow the mighty do as they please and force the weak to suffer as they must. On the other hand, Thucydides illustrated the Cold War phenomenon of “polarization” among states, resulting from their strategic interaction (Doyle, pp. 204-205).

The impact of Thucydides’ work upon scholars of the Cold War period consists evidence for the relevance of his realist theory in today’s world. In fact, while his Peloponnesian War is chronologically distant from the present, Thucydides’ influence upon realist scholars in the post-1945 period, and in turn upon American diplomacy, is direct (Pallotti, p. 149).

Specifically, the foundations of American diplomacy during the Cold War with regard to the struggle between the two superpowers and the ethical consequences or problems posed for smaller states caught in the middle of bipolar competition are derived from his work.

Writings of the early Cold War years often derive their inspiration from Thucydides’ work. This period witnessed the generation of a significant body of theoretical literature that finds in the Athenian-Spartan competition a precedent to the Soviet-American bipolar competition. Structural realists such as Kenneth Waltz and Robert Gilpin found that the Hellenic world, and particularly the relationship between Athens and Sparta, as Thucydides describes it, provided an allegory for the Cold War polarization. In 1947, Secretary of State George Marshall had called attention to the significance of the Peloponnesian War for an understanding of the contemporary world,

I doubt seriously whether a man can think with full wisdom and with deep convictions regarding certain of the basic issues today who has not at least reviewed in his mind the period of the Peloponnesian War and the fall of Athens (Doyle, p. 208).

Moreover, during the polarization of the Cold War period, policy-makers equated America’s power to Ancient Athens’ glory, as told in The Peloponnesian War. Thus, in 1952, Louis J. Halle, at the time Director of the State Department’s Policy Planning Staff, wrote:

…the present, in which our country finds herself, like Athens after the Peloponnesian wars, called upon to assume the leadership of the free world brings Thucydides virtually to our side… It seems to me that since World War II Thucydides has come still closer to us so that now he speaks to our ear (Doyle, p. 211).

Throughout the Cold War, scholarly work focused on the conclusions that Thucydides drew from his study of power and competition in bipolar systems. The contemporary interpretation of the Peloponnesian War paraphrases what realists have come to term the “security dilemma”: as the power of a subordinate state in a relatively stable international system increases disproportionately, it is brought into conflict with the dominant states or states. The struggle between these contenders for preeminence and their accumulating alliances lead to a bipolarization of the international system (Doyle, p. 212).

Accordingly, a zero-sum situation results, in which one state’s gain is the other state’s loss. As bipolarization proceeds, the system becomes increasingly unstable, and so does the likelihood of system-changing conflict (Doyle, p. 213).

Indeed, the study of polarity in the Hellenic world in the period between the Persian and Peloponnesian wars has influenced the work of realist authors such as Robert Gilpin, Kenneth Waltz, Joseph Nye, and John Mearsheimer. In turn, this has also influenced American diplomacy as reflected in the work of Louis Halle in the 1950s, and Henry Kissinger, not only in the doctoral thesis, but during his role as Secretary of State in the 1970s. Specifically, reference of the parallel bipolarity of the Peloponnesian and Cold wars influenced the manner in which the U.S. saw the superpower world, and the manner in which it treated political developments and cultures in non-western regions (Pallotti, pp. 171-172).

As a result of his study of the Peloponnesian War, Thucydides drew a fundamental distinction between the mode of politics within a certain state and the pattern of political interaction among several states. This distinction that is still the subject of intense debate in foreign policy circles. Within a state, citizens enter a community based on a form of social contract, which provides the protection of laws at the expense of some individual freedom. As a result of the legal equality with which the social contract provides the citizens, the weak are able to withstand the strong and ethical considerations are respected. In the international realm, however, there is no social contract among citizens of different states, and, consequently, there are no laws to defend legality and morality of state interactions. Thus, in interstate relations, it is the strong who decide how the weak should be treated, as moral or ethical judgments are virtually nonexistent. This distinction between the ethics of domestic and international relations are implicit in the “Melian dialogue.” Here, Thucydides had Demosthenes, the Athenian orator, specifically contrast the affairs of a city-state, where laws and customs exist to treat weak and powerful equally, with international disputes, where the strong coerce the weak (Doyle, pp. 216-217).

Demosthenes is not the only one, however, to identify the place of justice and ethics in domestic relations and their absence in interstate relations. In his Politics, Aristotle accused individuals for having double standards. While they might restrain from behaving in an unacceptable way with regard to their fellow citizens, in the case of outsiders it is a different case entirely. He wrote,

…most people seem to think sheer domination is what is appropriate in the political sphere; and they are not ashamed to practice in regard to outsiders what they recognize is neither just nor expedient in their dealings with each other as individuals. For their own affairs, among themselves, they demand an authority based on justice: but in regard to outsiders justice is no concern of theirs.” (Doyle, p. 210).

Moreover, later writers have endorsed Thucydides’ argument that “might makes right.” Later realists, such as Machiavelli and Hobbes, agree with Thucydides that “might makes right” is an intoxicating concept for states to indulge in. Also, like Thucydides, these later realists suggest that, although Ethics has its own proper sphere within the community of a certain state, the attempt to regulate interstate relations according to similar precepts contains the risk of justifying cases of intervention in a sovereign state. As the contemporary theorist Hans Morghenthau puts it, the mixture or morality and foreign policy is a very dangerous one.

Throughout the Cold War period, as a result of America’s zero-sum competition with the Soviet Union for the worldwide balance of power, the US justified intervention in regions such as Latin America, the Middle East, Africa, Asia, and the Mediterranean, with the objective of denying communist influence. The critical importance of interventions for American interests overrode any sense of “immorality” that American support for anti-communist and often brutally undemocratic regimes may have caused. In short, concern for the customs and privileges of civil society in the United States was often not extended to cultures and countries whose political allegiance risked to upset the Cold War bipolar balance. One needs only refer to American adventures in Iran, Greece, Egypt, El Salvador, Guatemala, and Nicaragua, to name a few (Pallotti, p.178).

Thucydides may have been the father of a cruel realist view of international relations, but this does not mean that Thucydides himself endorsed the immorality of the international realm. Rather, if one accepts the distinction between internal and external affairs in The Peloponnesian War, it becomes clear that, when Thucydides deals with the relations of individuals within the state, he is indeed ready to make moral judgements. In his reproduction of Pericles’ funeral oration, one does not hesitate to comment on the tragedy of the plague that befalls Athens. Furthermore, in the debate prior to the Sicilian expedition, Thucydides did not hesitate to compliment Nicias for his sense of morality, by saying that “[Nicias] had ordered his whole life by high moral standards.” Of Nicias’s cruel and unjust opponent Alcibiades, he wrote, “his way of life made him objectionable to everyone as a person, and thus [the Athenian people] entrusted their affairs to other hands.” Finally, of the oligarchic coup that swept Athens after the exiled Alcibiades collaborated with the Persians and Spartans to dissolve democracy, Thucydides stated that democracy had been, in his experience, the best government Athens had had; its composition, of the few as well as the many, had been truly representative (Doyle, p. 217).

There have been, however, some misleading misinterpretations of Thucydides. For instance, Thomas Hobbes, great admirer of Thucydides, seriously misinterpreted the historian when it suited his political interests to do so. He wrote, in fact, that the ancient historian “least of all liked democracy” and “best approved of regal government.” Moreover, some classical scholars are uneasy with the conclusions that have been drawn by contemporary international relations theorists relating to the fifth century BC and the Peloponnesian War in to the events and developments of the Cold War. “We have been presented lately with an up-dated version of the Thucydidean thesis that the war was the inevitable outcome of the division of the Greek world into two power blocs. In its new guise, the Thucydidean view is fortified with the weapons of modern social science. The condition that troubled the Greek world and brought on the war is discovered to the ‘bipolarity.’ Typically, such words are borrowed from the physical sciences to lend an air of novelty, clarity, and authority to a shopworn, vague, or erroneous idea” (Doyle, p. 228).

The twentieth century was that period of history that witnessed the birth of many political ideals such as liberty of all countries, freedom for all nations, and the desire to bring all kinds of war and destruction to an end. Ironically, it was the US that stood as a symbol for all these ideals and values. However, in application, the US has not been much better than other aggressors of history, that is, illustrating the model of superpower that Thucydides himself described. Aggression and intervention represent the core of American foreign policy in the twentieth century, a policy which is directed by self-interest and basically, the principles of realism as defined by Thucydides, to a great sense, resembling the system of interrelations between Sparta and Athens.

When the US entered World War I under the leadership of President Woodrow Wilson, it was perceived by its western allies as an idealistic country that was looking for the freedom of other countries. The US entered the war to aid Britain against German and its allies. Wilson stated the objective of the US when he said, “We will make the world safe for democracy” (Farah, p.704). It is this statement that justified American intervention in World War I, an attempt to bring peace back to the world under a system that respected popular struggle, liberty and democracy. Wilson’s motto of “self determination of peoples” became the motto of American intervention in World War I, but at the same time, it eventually became the shell behind which was hidden the US realist foreign policy (Snell, p.3).

Similarly, the US announced in 1941, shortly before joining the war, that “the right of people to choose their own forms of government was recognized” (Snell, p. 76).

Realism in America’s foreign policy is best illustrated by Sir Winston Churchill, the British Prime Minister during World War II, who confessed that the US was by no means forced to drop two atomic bombs on Japan to make the latter surrender. Churchill doubted that “President Truman and most of his chief advisers¾particularly Mr Stimson and General Marshall, the US Army’s Chief of Staff¾were now as intent on using the atomic bomb to accelerate Japan’s collapse as Stalin was on entering the war against Japan before it ended, in order to gain an advantageous position in the far East” (Hart, p. 695).

Churchill justified the American dropping of two nuclear bombs on Japan, killing thousands of innocent citizen with political interests, “It is quite clear that the United Sates do not at present time desire Russian participation in the war against Japan” (Hart, p. 697).

The US was, therefore, aware that sooner or later, it was going into a race against the USSR in a system similar to that illustrated by Thucydides. By putting an end to the war in Japan, regardless the ruthless means, the US prevented the USSR from sending troops to Japan or the region, namely through an early Japanese surrender.

Moreover, by using the nuclear weapon, the US wanted to convey a message of threat to the USSR. The American policymakers used atomic power in Japan in order to force the Soviets back on all fronts. President Truman realized that he had a golden opportunity by monopolizing the nuclear weapon because “this monopoly provided him with an ‘umbrella’ under which he could, without running too many risks, pursue his policy of firm resistance to any Communist advance beyond the ‘iron curtain’ that had fallen across Europe at the time of the German surrender” (Fontaine, p. 267).

Henceforth, the ideals upon which the US based its decision to enter the war were now replaced by political interests, namely interests imposed by the political realist perspective that dominated American foreign policy makers during that period. The thousands of innocent victims of the atomic bombs in Japan simply counted as figures to be added to the harvest of war.

Accordingly, the modern foreign policy of the US is based on one fact: America’s inability to survive politically, economically or socially without living off the rest of the world. Under the cover of providing help and support, the US has interfered in the affairs of other nations, and the actual reasons that stand behind the provided support, are but the desire to fulfill the self-interests of the US. It does not take a historian to realize how similar the US foreign policy was to that of Athens during the Peloponnesian Wars, especially towards the weaker neighbors of Athens whom the Athenians feared would shift alliance towards Sparta (Macdonald, p. 2).

Even before World War II came to an end, American officials at the highest levels were aware of the changes taking place in the international system. The first official American reference to this situation where the US was involved in rivalry against the Soviets was made by General Patton, when he “called on the world to prepare for the ‘inevitable Third World War” (Fontaine, p. 299).

Governed by the interests of its industrial, economic and other influence groups, the US can be seen as a power of interests. Immediately after World War II, the US interests became threatened by the fast growing Communism coming from the Soviet Union. Like the US, the USSR was also victorious in the war, and it also had become a major power. The differences between the US and the USSR were not only over politics, but also over ideology and economics, differences that were sufficient to lead to rivalry between the two superpowers. The USSR was calling for the spread of socialism which could never be compatible with the American capitalist ideology of interests and power. In addition to this, the USSR was looking forward to becoming the leading revolutionary force in the world, which would threaten the stability of the America’s political and economic interests. American extremist position with respect to the Soviet rivalry is best exemplified by General Patton, a statement that forced his seniors to send him to retirement when he declared that his armies were ready to march to Moscow (Fontaine, p. 299).

Thucydides’ theory on the Balance of Power becomes very significant when studying the politics of the Cold War between the US and the USSR. The significance of such an examination is found in the parallels that have been made between the Peloponnesian War and the Cold War. Moreover, practical consequences of such views, ancient as they are, are clearly witnessed in American diplomacy in the Cold War era with regard to the relationship between the superpower balance and regional politics in those regions over which the US and the Soviet Union competed.

Both the US and the USSR did not want to get involved in a war against each other, especially that the consequences would be destructive for both sides. Both countries possessed nuclear and destructive weapons. Both had the most powerful armies in the world. As a result, a war between the two powers was not allowed. Instead, the hostilities between the two countries would be fought on other grounds, namely those of poor and under-developed countries of Asia and Africa, a fact that eventually became central to the Balance of Power policy. These countries, known as third world nations were trying to be independent, but they were relied heavily on major powers, especially the US for their economic and social development. Having its interests threatened by the growth of communism, the US would not allow any third world government to adopt communism (Fontaine, p. 244).

As the world alliances divided between East and West, the US set its new foreign policies according to the strict objective of preventing communism from spreading into other countries (MacDonald, p. 2). Having the strongest military power, the US was willing to protect its interests and to enforce its presence through the use of this power when necessary. According to this policy, the US found itself involved in a number of world events and disputes such as the Korean War, the Vietnamese War (Gurtov, p. 126), and later on the Gulf War. In these three wars, the US tried to look as though it was fighting to protect the rights and interests of the nations involved in these wars. In reality, the US was only protecting its own interests, without any consideration of the interests of other nations.

During World War II, the US and the Soviet Union invaded Korea which was then occupied as a Japanese territory. The Soviets occupied the Northern part of the peninsula while the Americans occupied the Southern part. After the war, both the Soviets and the Americans withdrew after establishing government systems that supported them. Relations between the divided sectors of the country were very difficult, especially as the USSR and the US maintained influence over the two governments. As a result, in June 1950, relations were severed and North Korea invaded South Korea. The US had very vital interests in the region which was becoming into one of the most important American spheres of influence (Fontaine, p. 245).

In South Korea, the American maintained a considerable military and political presence by which they influenced the whole region. If South Korea was converted to communism, this would lead to several catastrophic consequences for American interests. As North Korea refused to withdraw its forces, the US immediately led the United Nations forces in a war against the North Koreans and later against the Chinese who were supporting the communist regime in the North. In the eyes of the world, the US was leading a peacekeeping force whose objective was to maintain peace in the region and to push back the assaulting party back to its territories (Fontaine, p. 253).

From the Thucydidean perspective, the US was making sure that its interests in the Far East were secured and that its rival, the Soviet Union, would not be able to expand in that region. By getting involved in the war to liberate South Korea, the American government took on itself the responsibility of defending its ally as well as its own interests in the region, to the extent of launching a full war against North Korea and getting involved with China in possible widely spread war (George, pp. 125-126). Involvement in South Korea could have been very painful to the US, especially that China was supporting the North Koreans with troops and ammunitions. The US was ready to sacrifice 150,000 American casualties in order to stop the communist assault on South Korea. American interests in and with South Korea were the criteria upon which the US made its decision (Fontaine, p. 16). To protect its interests, the US could have gotten involved in a wide-scale war against China, especially as General MacArthur wanted to “severely cripple and largely neutralize China’s capability to wage aggressive war and thus  save Asia from the engulfment otherwise facing it” (Steele, p. 37).

The same American readiness to sacrifice lives and money to support an ally was seen a decade later when the US intervened in Vietnam to make sure that the communists would not control South Vietnam. American Secretary of State John Foster Dulles explained the Thucydidean policy of the US in Vietnam, saying that its aim was “to reduce the strength of Communist Parties and other pro-Soviet elements” (Short, p. 111).  Hence, the major aim of the US was not to protect democracy in Vietnam, but rather, to prevent the Communists from gaining control, even if Vietnam as a country and a system was totally destroyed (Short, p. 105). US policy makers had to work under a legal cover in their intervention, “The president is authorized to employ Naval and Air Forces of the U.S. to assist friendly governments of Asia to maintain their authority as against subversive and revolutionary efforts fomented by communist regimes, provided such aid is requested by the governments concerned” (Pfeffer, p. 122). This statement made by Dulles in 1954 shows that the US was intending to intervene in Vietnam. South Vietnamese official request for US intervention was already secured, since this regime could not stand on its own without American aid against the attacks of the opposition, the peasants and finally, the communists from the North. Intervention in Vietnam, however, did not prove to be a successful operation, and the war there continued to linger from 1954 until 1976, a long struggle during which the US kept about half a million troops in the region. The US losses were more than 22,000 killed, hundreds lost and several thousands handicapped (Short, p. 315).

The end of the Cold War requires a re-examination of Thucydidean scholarship and the theories of interstate behaviors that are derived from his work. Furthermore, if there is to be a new world order, the United States must recognize that the dynamics of interstate relations are constantly fluctuating. While there may be certain constants in the behavior of states and individuals, the possibilities for interaction, cooperation, and conflict are always constant, and often present themselves in new and previously unknown forms. In this case, the study of history is only a guide, not a prescription. Thucydides may not have been shocked if he had lived to witness the Cold War and its realist rivalry between the USSR and the US, but had he come back to life today, he would certainly want to make revisions to his observations and thoughts.


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