How America can avoid the ‘Other Thucydides Trap’

The holiday season is a time for coming together. It’s a time to think of those close to us, but it’s also a time to reflect on the larger sphere of which we are but a part: our community, our country and the power above. To them we owe our freedom. And in this season, we should also remember that freedom requires friendship: a healthy democracy requires debate, but with too much disunity, things fall apart. 

Americans are becoming aware of this. A respected pollster this year found that nearly half of the country thinks that civil war is coming. Opinions may be cheap in the digital age, but the number is still striking. Nor is it surprising — not given the amount of political violence in the last two years. It’s far from the democratic ideal. 

Not only does disunity hurt us at home; it weakens us abroad. Countries know that it’s cheaper to stoke division in a rival’s society than to go to war. The United States has often supported domestic opposition groups in foreign rivals, from Soviet dissidents to pro-democracy protestors in the Arab Spring. Likewise, our competitors interfere with American elections and give at least verbal backing to protesting groups here, both on the right and the left. 

But don’t take it from me; Thucydides said it long ago. The irascible old man wrote “The Peloponnesian War” around 400 BCE. A general exiled from his home in Athens as punishment for defeat, he spent the next two decades chronicling his country’s downward spiral. He described a war that lasted 27 years and brought misery across a wide canvas, stretching from Sicily to what is today Turkey.  

The result was a classic book, but not one full of cheer. An index of Thucydides’s mood: He wrote the word “love” only twice in his 500-plus pages, and then only in reference to popular passions. His subject was war in all its horror.   

In recent years, Thucydides has surprisingly made the headlines. “The Thucydides Trap,” a theory by Harvard Professor Graham Allison, warns of the danger of war when a rising power threatens an established power. Thucydides wrote about the rivalry between Athens and Sparta. But substitute China, a rising power, for Athens, and substitute the United States, an established power, for Sparta, and you have today’s world.  

The trap, in Allison’s opinion, is war. It’s an awful prospect, and it is understandable that the Chinese ambassador to the United States mentioned the danger of the Thucydides Trap. Scholars disagree about which is more dangerous, an established power that feels threatened or a rising power feeling its head. 

But in any case, there is a different issue. Let’s call it the “Other Thucydides Trap.” 

The Other Thucydides Trap is the failure of a free society to set limits. Athens is the classic case. Athens began the war as the favorite. It had Greece’s strongest economy, its biggest navy, its largest alliance and its most dynamic and educated population. Yet by war’s end, Athens had lost everything. Walls, fleet, alliance — all were gone. The economy was a shambles and the demographic losses from disease, desertion and battle casualties were enormous. No wonder Thucydides makes such grim reading. 

Yet Thucydides doesn’t give Sparta credit for winning. The war, he says in effect, was Athens’ to lose, and it lost it. The reason is simple: the home front. Sparta was an oligarchy and a closed society. It managed to hold its ruling class together during the long conflict.

But Athens was a democracy, and its leaders turned on each other and stoked popular divisions. Eventually political debate grew so contentious and the blame game so bad that a coup d’etat briefly took power; civil war was barely avoided. Yet Athens recouped and kept fighting for nearly another decade.  

“The Athenians did not finally succumb until they fell the victims of their own internal disorders,” Thucydides writes. Sparta didn’t win the war; Athens lost it. Athens defeated itself because its leaders could not come together for the good of the whole. 

Scholars may debate whether Thucydides was right. He may underrate Sparta or overdo his criticism of the masses. Yet on one point, Thucydides is indisputable: Too much internal division weakens a society beyond the point of no return.  

Americans need to remember that our rivals have an interest in seeing us divided. With that in mind, we must balance disagreement with respect and solidarity. We don’t want a future historian to write a book about America’s defeat. We don’t want to be the subject of a study in which the word “love” barely appears. We don’t want to fall into the Other Thucydides Trap.  

Barry Strauss is a military historian and classicist at Cornell University and the Corliss Page Dean Fellow at the Hoover Institution. He is the author of “The War That Made the Roman Empire: Antony, Cleopatra, and Octavian at Actium” (Simon & Schuster, March 2022).