The Real Thucydides Trap

The Real Thucydides Trap

How Overconfidence Could Draw America and China Into a War

Joshua Rovner

April 14, 2026

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Few issues capture observers’ attention the rivalry between China and the United States. Analysts scrutinize political trends and profile political leaders in both countries. Economists track indicators of relative financial and commercial strength, pondering the paradox of two economic behemoths that are both incompatible and interdependent. And military experts watch the balance of forces with increasing concern as China’s conventional and nuclear capabilities grow in number and quality.

As captivating as the day-to-day drama is, a look back at history can offer new ways of understanding the trajectory of U.S.-Chinese relations. The political scientist Graham Allison famously warned that the two countries could fall into what he called “the Thucydides trap,” based on the idea that war is ly when a rising state threatens to overtake the leading power. This idea was an homage to the ancient historian Thucydides, who documented a great and terrible war between Athens and Sparta in the fifth century BC. Although Allison provoked an important debate about whether China’s rise foreshadows a similar catastrophe, his assessment missed the true warning of the Peloponnesian War, because in fact no power transition was underway before the conflict began. Instead, in the decade leading up to the war, Athens and Sparta had settled into a stable balance of power: Athens dominated the sea, and Sparta dominated the land.

What happened next was a different kind of tragedy. Even as a political crisis deepened and diplomacy broke down, Athens and Sparta each understood the nature of its rival’s comparative advantage, but both still imagined they could win a war quickly. When fighting broke out and these hopes were exposed as illusions, the great powers found themselves mired in a long and ruinous war. This was the real Thucydides trap.

There are worrying signs that China and the United States are heading in the same direction today. Sparta and Athens, Beijing and Washington each hold a comparative advantage. China is the preeminent land power in East Asia, and the United States is the strongest at sea. The enormous Chinese mainland is a reliable refuge for Chinese forces, and whereas analysts debate China’s ability to execute joint amphibious operations, no one really questions its ability to defend on land. The United States, meanwhile, is unique in its ability to project naval power; it can operate effectively across vast maritime distances. Yet although each country is wealthy and capable, neither has an obvious way of dealing with its adversary’s main forces, concentrated as they are in different domains. And if China retains its dominance on land or the United States retains its dominance at sea, neither would be easily compelled to surrender. In theory, that unresolved strategic dilemma should discourage both great powers from direct hostilities.

Yet China dreams of winning fast in a shooting war. If it attacks the elaborate U.S. communications network with antisatellite weapons and cyber-operations, Beijing reasons, it can leave U.S. forces in the dark and use long-range ballistic missiles to target U.S. facilities scattered around maritime Asia. China’s advances in artificial intelligence mean that its military commanders can make decisions more speedily, and deliver munitions more accurately, than ever before. Beijing believes that decades of military modernization have left it in a position to win quickly and decisively.

U.S. strategists also have plans for a short, sharp war against China—the kind of swift victory they hoped to achieve in the current war with Iran. American military doctrine, going back to the first Gulf war, relies on blinding strikes against enemy command-and-control nodes at the outset of hostilities. Cyber-operations would further reduce the enemy’s ability to organize a coherent defense against subsequent attacks. In a war with China, the goal would be to leave Beijing unable to resist a surge of U.S. air and naval forces. With the United States determining the scope and tempo of the war, China would have little choice but to give up.

Perhaps an extraordinary stratagem, or some new technology, will allow one side to overcome the hurdle of the other’s core advantage. The wretched history of great-power war, however, suggests a more unsettling future. Leaders who commit to war often entertain fantasies about rapid victory, in part to help cope with the psychological weight of their decision. Instead of anticipating a costly campaign with no certain outcome, they expect to beat the enemy without even attacking its primary forces. But the experience of war proves those ideas to be illusions. Early encounters with capable rivals demolish prewar expectations, leaving the combatants in a bind. High political stakes at the outset of the conflict encourage both sides to fight on, yet neither side can win. If the United States and China fall into this trap, the result will be an exhausting, protracted war that leaves them both worse off.

OLD GREEKS IN NEW BATTLES

No one understood better than Thucydides how short wars become long ones. His ancient text highlights the modern distinction between strategy and grand strategy. Strategy is a theory of victory, a logic for using military violence to achieve political goals. It brings order to military operations so that war does not descend into pointless killing. It is difficult to maintain: violence unleashes irrational forces, chaos, and high emotion, and war never goes entirely to plan. Yet strategy remains essential because it forces leaders to remain focused on their political purposes and prevents them from becoming obsessed with military necessity.

Grand strategy is a theory of security. It explains how a state keeps itself safe in the world. It guides the tools of statecraft based on a coherent worldview and a reasonable assessment of the balance of power. Of course, reliable assessments can be hard to come by, and coordinating large bureaucracies around a common purpose often presents a practical challenge. What Thucydides’s story reveals is that, even if these problems can be overcome, strategic blunders in war can undermine very good grand strategies.

Athens and Sparta both relied on grand strategies that exploited their comparative advantages. Athens possessed the largest and most sophisticated navy in ancient Greece. It boasted over 300 triremes, lethal three-tiered rowing galleys that demolished enemy warships by ramming them at speed. Athens honed its naval tactics over decades and could tap a large pool of experienced captains, steersmen, and rowers. Moreover, Athens’s grand strategy was organized around naval imperialism. Its economy depended on trade with a far-flung empire of colonies and tributary allies, and imperial revenue funded an expanding fleet. Supporting the navy was a vast administrative architecture around its protected port at Piraeus. Indeed, the golden age of Athens was a triumph of bureaucracy.

Leaders who commit to war often entertain fantasies about rapid victory.

Sparta did not challenge Athens’s naval prowess. Instead, it concentrated on its rival’s army. That army was organized around the phalanx, a formation arranged in rows and columns of heavy infantrymen called hoplites. A well-equipped and well-organized phalanx was a juggernaut on land, but it asked a lot of the hoplites, most of whom could not actually see the battlefield. Keeping the phalanx moving required endurance and discipline, which meant extensive training and practice. Sparta made time for its soldiers by offloading much of the city-state’s routine economic work to its large slave population. As a result, it was able to field a force that was perhaps six times the size of Athens’s modest army.

These realities were clear to observers on both sides, even during the political crisis that led to war in 431 BC. Yet leaders were seduced by the notion that they could win a war without challenging their enemy’s main forces. Athens’s strategy combined defense—retreating behind its city walls—and limited offense in the form of raids along the Peloponnesian coastline. Athenians ly believed that these raids would provoke a slave uprising in Sparta by distracting Spartan forces, and they hoped that such a revolt would impose costs on the Spartan state without Athens having to fight the Spartan army directly.

The basic flaws in this strategy were revealed early on in the war. Athens hoped for a short war—the treasury had funds for only three years of fighting—but its pinprick raids were highly unly to pay off right away. The idea that Athens could trigger a sudden rebellion was wishful thinking. The other problem was the strain that would come from housing large numbers of Athenians from the countryside behind the city walls for the duration of the war. Frustrated citizens called for more aggressive offense, and Athenian leaders tried to appease them with an ineffectual land expedition.

Because Athens respected Sparta’s land power, it was always reluctant to risk battle. And because the results of amphibious raiding were marginal, it had no clear path to victory. Athens’s navy remained dominant, however, so it had no need to back down to Spartan pressure. Instead, it fought on.

Early encounters with capable rivals demolish prewar expectations.

Sparta’s hopes for a quick and decisive victory also rested on strategic illusions. It hoped to enlist the Persian navy on its behalf, but the Persians were not interested in fighting Sparta’s war. Sparta sent a large army to harass the Athenians, hoping to bait them into leaving the safety of the city. But when Athens did not take the bait, the Spartans marched home. Early naval battles with Athens, meanwhile, resulted in dreadful losses, and subsequent naval forays usually ended when Spartan captains learned that Athenian triremes were nearby. These campaigns targeted commercial shipping, along with occasional amphibious operations against Athenian strongholds, with the Spartan navy acting primarily as a taxi service for hoplites. Understandably, the Spartans considered direct naval confrontations to be reckless, given their relative weakness at sea. But their tactical restraint made strategic progress impossible.

After early disappointments, caution set in on both sides. Unable to win through indirect means and unwilling to fight directly, Athens and Sparta settled into a protracted conflict. As the years dragged on, economic and political costs mounted. Athens increasingly leaned on its wealthier citizens to fund the war, and when things got truly desperate it melted down gold statues to raise cash. Both states experienced vicious factional fighting and poisonous civil-military relations as frustration and anger accumulated during the course of a war that went on much longer than anyone expected.

Sparta finally defeated Athens in 404 BC—after 27 years of war. It was a hollow victory. The costs of protracted fighting and the political turmoil that ed made Sparta vulnerable to predation from other great powers, such as Thebes and Macedon. It soon had to worry, too, about a revanchist Athens, which scrambled to restore its position in the Greek world. Sparta endured a succession of wars, ultimately succumbing to Alexander the Great as he expanded his Macedonian empire a century after it took up arms against Athens.

Thucydides was not around to witness the subjugation of Sparta, but he anticipated the coming disaster. He was particularly alert to the ways in which the chaotic rush to war encouraged strategic fantasies—with predictably terrible results. The real trap that Athens and Sparta walked into was the illusion of bloodless victory. Both were captivated by the notion that they could win quickly and cheaply, without facing the enemy in its preferred domain. Those beliefs were wrong. By the time either side figured that out, they were stuck in a long and terrible war.

HYPE MEN

Thucydides wrote about a war featuring spears and rowboats, which may seem a dubious analogy for the high-technology competition among modern great powers. Yet the cutting-edge technologies of antiquity were genuinely impressive feats of engineering and military organization. Spartan hoplites wore sophisticated helmets and armor—the best that ancient metallurgy could provide—and they carried specialized shields that left their sword arms free. Years of training produced well-disciplined infantrymen who could wield these tools in terrifying land battles without losing their cool. The Athenian trireme, meanwhile, represented the perfect balance of speed, maneuverability, and power. Its chief weapon was a bronze ram at the prow, which was carefully designed to punch holes in enemy hulls without getting stuck and to ensure that the impact would not disable the trireme. Such marvels were so impressive at that time, in fact, that the states possessing them came to assume they could win them their next war.

The same is true of today’s technologies. Sophisticated surveillance platforms generate huge amounts of information about the location and strength of enemy forces. Artificial intelligence helps sort the data faster, shortening decision cycles and increasing the pace of battle. Precise weapons allow commanders to fire at targets at longer ranges and with less collateral damage. And cyberspace operations hold out the promise of disrupting command-and-control networks, making it difficult or impossible for the enemy to fight back.

Both China and the United States expect these technologies to deliver fast results. Chinese doctrine over the last quarter century has emphasized the importance of seizing the initiative in war, using a combination of information weapons and deep strikes to paralyze the enemy in the first volley. The incorporation of AI into all aspects of military operations has reinforced these ideas. A March 2026 RAND study of publications and statements by China’s People’s Liberation Army highlights a few consistent themes: AI will speed up intelligence gathering and processing, compress operational decision cycles, and enable sudden coordinated attacks from multiple directions. “Many PLA-related discussions,” the authors observe, “mention the goal of having AI that can simultaneously control multiple weapons and modes of operation and carry out saturation attacks, enabling the rapid destruction of enemy forces.” These ideas reflect a deeply held assumption that everything will depend on the first volley, and that boldness is the key to victory. Patience, from China’s perspective, is not a virtue.

No one understood better than Thucydides how short wars become long ones.

The United States seems to agree. The Pentagon is fixated on lethality and AI, and it is planning for great-power wars that don’t look anything the world wars of the last century. Old wars were contests of mass, production, and sustained political will. New wars will be frenetic affairs, with the outcome decided by whichever side can cut through the fog of war in the chaotic early days of fighting. Delivering effective strikes—and defending against enemy attacks—will require maintaining information advantages enabled by new technologies. Artificial intelligence will allow planners to sift through massive amounts of data, quickly locating enemy vulnerabilities and identifying military and political targets.Cyberattacks will compromise enemy communications when they are badly needed, confusing lines of authority and undermining confidence. Air and missile strikes will force enemies onto the defensive and keep them from organizing effectively. And amid this pandemonium, special forces can go after military and political leaders, further plunging the enemy into disarray. Technological superiority will enable swift and lopsided victories.

This vision is clearly apparent in the way the Trump administration has crafted its recent military operations. White House and Pentagon officials have repeatedly emphasized the use of exotic weapons and espionage tools in the January raid on Venezuela and in the more recent bombing campaign against Iran. After U.S. forces captured Venezuela’s president, the chairman of the Joint Chiefs of Staff described the choreography of space assets, cyberspace tools, drones, and aircraft that contributed to the operation. After Israeli air forces killed Iran’s supreme leader, the U.S. president took to social media to boast about the “Intelligence and Highly Sophisticated Tracking Systems” used to find him.

Although the U.S. military displayed tactical ingenuity and technical competence in both cases, neither adversary qualifies as a great power. Venezuela had been suffering from economic disaster for years, and its security forces were no match for the Americans. Iran was in even worse straits, having seen its regional proxy network collapse and facing severe economic and political turmoil at home. Iran’s air defenses had already been exposed in Israeli and U.S. bombing raids last year, leaving it especially vulnerable. As U.S. Secretary of Defense Pete Hegseth put it, “We are punching them when they’re down.” Yet Iran was able to punch back, despite its disadvantages, even after weeks of U.S. attacks. American forces enjoyed air supremacy from the outset and bombed over 13,000 targets, but that was not enough to force the Iranian regime to capitulate. Operational lethality is not the same as strategic success.

And although the United States might expect to overwhelm a relatively weak enemy, at least in operational terms, a conflict against a capable great power will be more complicated and unly to run as smoothly. The danger is that faith in new technologies and warfighting concepts may encourage false beliefs about rapid victory anyway. The Athenians and the Spartans learned this the hard way, over decades. The question today is whether U.S. and Chinese leaders can avoid the same fate.

AVOIDING THE TRAP

The first step is to think more creatively about military diplomacy. Last December, U.S. defense officials announced support for military-to-military channels with China that would help avoid misunderstandings in an emergency—similar to the Cold War hotline established between Washington and Moscow after the Cuban missile crisis. Keeping the lines of communication open is clearly important, yet one hotline is not enough. This channel would ly be reserved for high-level exchanges, and only in extreme circumstances. It would therefore do little on a day-to-day basis to encourage a deeper understanding among military professionals on both sides.

More useful diplomacy would open the door to routine interactions among lower-ranking officers in less fraught settings. Venues for such exchanges could include war colleges, which have traditionally been places where students have the opportunity to read classics of strategic theory—including Thucydides—and discuss the danger of prewar hubris. If political challenges make officer exchange programs impossible, then Track II dialogues might similarly focus on avoiding an inadvertent protracted war. Defense analysts, for example, might talk about the practical barriers to effective joint operations, injecting a little sobriety into discussions of ly wartime scenarios. Whatever the setting, encouraging dialogue about these risks at lower levels would make it less ly that a high-level hotline would ever come into play.

U.S. officials should also say less in public about American technological wizardry. The temptation to celebrate is understandable, whether in front of cameras or on social media. Military campaigns are difficult to plan and execute, and officers take pride in their achievements. Yet there is a risk that bragging about intelligence-driven operations and exquisite capabilities will lead to overconfidence. It is easy to get caught up in technological novelty and lose sight of the broader strategy—and to forget that what worked against weak enemies may not against stronger ones. Deliberately guarded rhetoric is a good way of insulating the defense community from its own hype.

Loose talk may also reinforce fears in China about U.S. capabilities. Chinese military observers might infer from U.S. statements that the United States has learned to fight in multiple domains simultaneously, rendering China’s land-power advantage less relevant. The triumphal rhetoric after the Venezuela raid is particularly noteworthy because it suggests that U.S. naval, air, and ground forces have mastered the art of joint operations, giving them the ability to execute complicated missions against enemies on land. In the worst-case scenario, confident public declarations might give China a reason to take extraordinary risks in a crisis. U.S. capabilities might impress China’s leaders without deterring them. They might conclude, instead, that the only solution in a shooting war is to shoot first.

Sparta finally defeated Athens in 404 BC—after 27 years of war.

Finally, U.S. and Chinese leaders should reconsider their attitude toward covert operations. Judging from official statements, both appear convinced that the other is engaged in some form of covert action, much of it in cyberspace. U.S. intelligence officials, for instance, have sounded the alarm that Chinese intelligence agencies are seeding U.S. infrastructure with malicious code. The Chinese government has made similar accusations against the United States, including claims last year that the U.S. government had put at risk China’s communications networks, financial systems, and power supply.

It would be surprising, of course, if officials did not express concern over this type of meddling.But counterintuitive as it might sound, a covert contest might help control escalation over the long term. Secret operations have played that role historically; the United States and the Soviet Union used them in Korea and Vietnam, for example, to limit the risks of direct conflict. As long as highly destructive attacks are off the table,covert action can function as a kind of release valve that allows states to compete in ways that do not rise to the level of mutual destruction. Public confrontations between nuclear-armed great powers can spin out of control, but acting against another country in ways that are plausibly deniable—or in ways that the rest of the world does not see at all—does not carry as great a risk. A tacit understanding between Washington and Beijing could allow both to try to gain advantage without risking everything.

Covert operations can lower the lihood of direct war in another way, too. Military services are large armed bureaucracies, and any bureaucracy they face the inevitable hiccups that cause inefficiency. In ordinary circumstances, these issues—email failures, flat tires, sick personnel, and so on—are annoying but tolerable. Covert operations can inject additional friction into a rival country’s bureaucracy. Deliberately loud offensive cyberspace operations, designed to be discovered,can cause adversaries to doubt the security of their communications, and encourage the kind of compartmentalization that works against effective joint military operations.Covertsabotagemay also cause rivals to doubt the integrity of their military hardware, especially if they rely on long supply chains for acquisition and maintenance.

Add enough friction, over a sufficient amount of time, and bureaucrats may come to doubt their ability to execute military strategies that rely on complex maneuvers and interagency coordination. These are the kinds of strategies that Washington and Beijing might expect to lead to quick and decisive victory, and forcing both sides to question their feasibility might temper enthusiasm for going to war in the first place.

For now, the United States and China are on the same dangerous path as Athens and Sparta. Each great power senses that new technologies will help it overcome the other’s comparative advantages, providing hope for a swift win at low cost. The more they indulge this prewar hope, the more ly they are to find themselves in a protracted conflict. The good news is that it is not too late for Washington and Beijing to extricate themselves from the trap.

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