The Risks and Rewards of Thucydides’ History of the Peloponnesian War


For a man so long dead, Thucydides is rarely out of the news. A recent Politico article discusses the influence of Thucydides and the Peloponnesian War on the Trump White House, with reference to Graham Allison’s recent briefing of the National Security Council on his new book, Destined for War: Can America and China Escape Thucydides’s Trap? White House Thucydideophiles reportedly include Stephen Bannon, James Mattis, H.R. McMaster, and Michael Anton.

Since 2011, the Thucydides trap has been Allison’s tweetable shorthand for the argument that an unexpected war between America and China is more likely than policymakers recognize. The “trap” coinage is drawn from Thucydides’ famous line about the outbreak of the Peloponnesian War — that “the growth of the power of Athens, and the alarm (or fear) which this inspired in Sparta, made war inevitable … or necessary or compulsory” — and is supplemented by Allison’s Thucydides Trap Project, which tracks instances of war between rising and ruling powers over 500 years. The book is making waves and being attacked and praised in almost equal measure.

As a scholar of Thucydides as well as a student and teacher of American foreign policy, I am generally gratified when anyone reads Thucydides for any reason whatsoever. Yet, as someone who has just published a book on the causes of the Peloponnesian War —  Thucydides on the Outbreak of War: Character and Contest — I find most of the articles explaining what Thucydides “really” means by his account of the origins of the war problematic, to say the least. Now, some of this is the academic’s narcissism of minor differences (I know this subject well and so have strong views about it), but it also raises a more substantive issue. How can or should Thucydides influence public policy? What does he actually offer? I want to discuss that issue generally by sketching the character and purpose of the History of the Peloponnesian War as I understand it, and then to conclude with a meditation on Allison’s Thucydides trap. (I should note in this context that I worked for Allison fifteen or so years ago as a research assistant, mainly on issues of nuclear security, though I have corresponded with him more recently about Destined for War, given my own research on the causes of the Peloponnesian War).

In our attention deficit inspired media landscape, preoccupied as it is with talking points, the History of the Peloponnesian War, that most difficult and richly rewarding of ancient books, has somehow become a stockpile of “authoritative” ancient wisdom, from which one can simply grab a choice line — the work is full of arresting and contradictory statements about international politics — and deploy it to score a point or bolster an argument. By quoting Thucydides, commentators wish to communicate sophistication, signaling something like, “that’s what the ancient wise man thought, and it’s what I believe, too.” The usual victim is the poor Melian dialogue, which inevitably suffers what it must.

Yet the History is more about unsettling the reader’s pieties than it is about confirming them. In my view, the book is intended to bring about a kind of political chastening, for it throws the multitude of errors that forever bedevil politics into vivid relief. In other words, part of its goal is to shape the reader’s vision of the possibilities but also the limits of political life. This is one of the reasons the work is of interest to political theorists. I also believe the History is intended as a vicarious political education for citizens, soldiers, and statesmen, communicated through the medium of the case study of a single, cataclysmic war — for war itself, as Thucydides says, is a violent teacher.

In the spirit of encouraging a deeper engagement with the History, I want to offer an introduction for how serious political people, military and civilian, might approach Thucydides profitably. It goes without saying that some will disagree with the below remarks, for one thing that manifestly characterizes the study of Thucydides is vigorous disagreement.

Some framing information will prove helpful for the reader.

First thing’s first: Who was Thucydides? Thucydides was an Athenian citizen, a younger contemporary of Socrates, a military man, a political exile and a profoundly astute observer of human events. His book, now known as the History of the Peloponnesian War, is arguably the greatest extant prose work from the great fifth century BCE flourishing in Greece, a masterpiece of Greek political thought, and a revealing study of the first democracy at war. Thucydides is also generally understood to be the first scholar of international relations avant la lettre: Thucydides, paleorealist or ur-realist. There is a cottage industry of articles about precisely what kind of realist Thucydides truly is, matched only by similar industries involving Machiavelli and Hobbes. (On Thucydides and IR, see David Welch’s provocative, “Why International Relations theorists should stop reading Thucydides.” For lucid discussions about the reception of Thucydides across disciplines, see Neville Morley’s Sphinx blog, which discusses the Thucydides Trap and much else besides).

What was the Peloponnesian War? The war we today call Peloponnesian — what historians sometimes call the second Peloponnesian War (this, the subject of Thucydides’ life work and the defining event of his life) — was a 27-year conflict between the two preeminent city-states of ancient Greece: Athens and Sparta. It was a long war, spanning the years 431 to 404 BCE, and an enormously destructive one. It ended with the defeat of Athens by Sparta, though Thucydides maintains that Athens ultimately lost the war more through civil discord at home than through the actions of her enemies – democratic “polarization”, then, is nothing new and clearly influences the soundness of a state’s foreign policy. For unclear reasons, Thucydides’ own work ends abruptly midsentence in 411 BCE, seven years before the actual end of the war — though, as I have noted, he does diagnose the causes of Athenian defeat. (On the basis of internal textual references, Thucydides is believed to have died somewhere between 399-396 BCE.)

Who were the war’s contestants, and what was the character of their contest? In 5th Century Greece, Sparta was the preeminent land power, the leader of the Peloponnesian League — a primarily defensive alliance of mainly oligarchical cities. Athens, by contrast, was the preeminent naval power, a democracy, the first democracy, in fact, and the possessor of a great empire. Athenian democracy, however, was not a representative one like those today but rather a direct democracy, something closer to an illiberal democracy. Athens’ navy was unmatched, and because of her great walls — which stretched down to encircle her military harbor, the Piraeus — the city was unassailable by land. Athens was then a naval empire, and she dominated the islands of the Aegean while also harboring a thirst for imperial expansion. In addition to the comparative material advantages of the sides — their hard power, as we would now call it — the cities also had deeply opposing characters. Whereas Spartan power was long-standing and Sparta a deeply conservative or maintaining power, Athenian power was relatively new and Athens was a progressive, acquisitive city — a daring, expansionistic power.

What is Thucydides’ enterprise in his recreation of this war? Why did he write about it in the first place? Contrary to what you might think from everyone’s free use of the title the “History of the Peloponnesian War,” Thucydides did not write a work entitled a “history.” This is merely the title handed down to us. Indeed, in my view (one unsurprisingly not shared by the majority of ancient historians), the conceptual freighting attending the word “history” risks obscuring the character of the Thucydidean project as he himself seems to have understood it. Thucydides writes that he intends his book to be a “possession for all time” on the ground that the future will resemble the past. But how can a past thinker really assert that his work will be a possession for all time — or “for everlasting,” to use Thomas Hobbes’ felicitous translation of the key line?

According to Thucydides, there is some bright thread of human nature which runs through the differences characterizing different historical moments. History as a singular chain of events will not repeat itself, of course. Nonetheless, certain episodes of the History are intended to disclose universal phenomena. Think of a fable by way of example: The story and the lesson are virtually inseparable. Similarly, episodes in Thucydides are vehicles for insights or lessons, but they really can’t be separated from the narrative itself, which is one reason why excerpting lines from Thucydides (or, more often than not, from his characters) is so problematic. How does one know Thucydides endorses the view in question — such as that of the Athenian ambassadors at Melos — and, relatedly, how does one separate the meaning of a single line from the political situation in which it is embedded?

The History is composed of speeches and deeds (or narrative) which corresponds to our own experience of politics. Think about it for a moment: What is politics itself, domestic or international, if not talk, action, and their interrelationship? And talk can be cheap, but it need not always be cheap. Moreover, just as in the commonplace expression “actions speak louder than words,” we must examine the History’s speeches in light of the deeds and vice versa. For the work is a masterpiece of political rhetoric, with Thucydides subtly assisting the reader in separating out the rhetorical from the real in the speeches of his characters.

To bring all of these points together, Thucydides’ account of the causes of the Peloponnesian War is intended to shed light on the recurrent, human causes of war. And this is the subject of my own recent research: How the text works to communicate this more general teaching through a series of particular events or episodes, through the dynamic interrelationship between speeches and deeds in Thucydides’ involved account of the origins of the Peloponnesian War — or through the History’s brilliant exploration of how human attitudes, plans, hopes, and fears confront the moving, often uncontrollable world of political reality.

To state the issue in a slightly different way, the series of events Thucydides depicts in his important first book — the fuse snaking toward the powder keg of the Peloponnesian War — is designed to bring out what is characteristic or representative about it. In contemporary parlance, his account of causes of war is an artfully constructed case study, one revelatory of certain essential dynamics at play in the outbreak of wars. And, indeed, the case study method itself continues to be used to train decision-makers. Why? Because some actors make good decisions amidst conditions of uncertainty, when the stakes are high and the outcome uncertain, while others do not. And we want to learn from those who respond adeptly (or appropriately) to the demands of their moment, but also from those who fail to do so. For this pedagogical purpose, there are few resources better than Thucydides’ History of the Peloponnesian War.

Now, one of the best things about Thucydides is that he precedes our neat division of the world into academic specialties — history, international relations, political theory, etc. — but one of the worst things about Thucydides is that, well, he precedes our division of the world into these same specialties. The translation of Thucydides into the idiom of contemporary political science is especially tricky. (Here, the work of the political scientist Ned Lebow on Thucydides deserves honorable mention).

Does Thucydides intend his statement about the “inevitability” of the Peloponnesian War — this, the inspiration for Allison’s Thucydides trap — as a law-like generalization on the model of the social scientist? Not exactly. I do think that he is making a useful distinction between proximate and deeper causes — i.e., the precise events leading to war and the more fundamental issue of Athenian power — but, at the same time, he is also showing the reader how the angle of vision of the actors led to the conflict. The story is as much about Athenian and Spartan perceptions of their interests as it is about systemic alterations in the balance of power.

I maintain that Thucydides does not mean inevitability as efficient causation, or in any sense that suggests that the forces involved are fully external to the actors. Instead, I argue that the objective inevitability of a Peloponnesian War is in fact the product the subjective views of the actors themselves, rooted in the deeply opposing characters of Athens and Sparta, or in the ways that the cities differently privilege security, honor, and profit. To abridge a complicated story, what Thucydides means by necessity is perhaps best understood as the imperatives of the national interest, as the actor in question understands those interests, while these interests are themselves conditioned by overarching world views or disparate cultural outlooks.

To draw these threads together, a Peloponnesian war became “necessary” when the actors themselves came to see no alternative to it. This does not mean that they were correct to arrive at that decision, or that there were no alternatives to war. Instead, Thucydides illuminates the interactive chain of events by which the protagonists themselves became locked into path dependencies, firmly convinced of the reasonableness of their actions or policies, which, in fatal combination with one another, led to a mutually destructive war.

Are there lessons here for the United States and China? I think there are. Allison is surely right to maintain that structural stresses associated with the balance of power will test the U.S.-Chinese relationship in both expected and unexpected ways. He is also correct that this dynamic will be of vital importance for global order in the 21st Century, and that policy-makers would do well to be alive to the clear and present danger of miscalculation, or of the unintended escalation of minor conflicts. The United States and China all too easily risk becoming locked into dangerous path dependencies, rooted in opposing U.S. and Chinese perceptions of the imperatives of their harder interests — their necessities, to deploy Thucydidean lingo — as these meet concrete strategic areas —  such as, for instance, China’s sovereign claim over islands in the South China sea, the so-called Spratly chain, and the United States’ equally firm commitment to freedom of navigation in the same region, among other combustible issues. Or, to give a very recent example, North Korea’s sabre rattling test of a missile apparently capable of reaching Alaska.

But, of course, no Thucydides will solve our problems for us. The History reveals the characteristic ways that human beings succeed, or more often than not fail, to respond to the exigencies of their circumstances, for error, unfortunately, predominates over sensible judgment in human affairs. Insofar as Graham Allison is exhorting the United States and China to avoid gratuitous strategic errors, his advice, I would suggest, is soundly Thucydidean. Decision-makers in both countries would do well to heed him. For what is lost by caution — or, to use a favored Greek term, moderation — and a corresponding aliveness to the danger of clashing interests in the shadow of broader shifts in the balance of power? In great power politics, an ounce of prevention is surely worth a pound of cure, for if the plague to be cured is war, the disease has already progressed too far.


S.N. Jaffe is an Assistant Professor of Political Science and International Affairs at John Cabot University and the author of Thucydides on the Outbreak of War: Character and Contest (Oxford University Press, 2017).

Image: Rufus46, CC