Based on the current trajectory, war between the United States and China in the decades ahead is not just possible, but much more likely than recognized at the moment. Indeed, judging by the historical record, war is more likely than not. Moreover, current underestimations and misapprehensions of the hazards inherent in the U.S.-China relationship contribute greatly to those hazards. A risk associated with Thucydides’s Trap is that business as usual—not just an unexpected, extraordinary event—can trigger large-scale conflict. When a rising power is threatening to displace a ruling power, standard crises that would otherwise be contained, like the assassination of an archduke in 1914, can initiate a cascade of reactions that, in turn, produce outcomes none of the parties would otherwise have chosen.

War, however, is not inevitable. Four of the 16 cases in our review did not end in bloodshed. Those successes, as well as the failures, offer pertinent lessons for today’s world leaders. Escaping the Trap requires tremendous effort. As Xi Jinping himself said during a visit to Seattle on Tuesday, “There is no such thing as the so-called Thucydides Trap in the world. But should major countries time and again make the mistakes of strategic miscalculation, they might create such traps for themselves.”

* * *

More than 2,400 years ago, the Athenian historian Thucydides offered a powerful insight: “It was the rise of Athens, and the fear that this inspired in Sparta, that made war inevitable.” Others identified an array of contributing causes of the Peloponnesian War. But Thucydides went to the heart of the matter, focusing on the inexorable, structural stress caused by a rapid shift in the balance of power between two rivals. Note that Thucydides identified two key drivers of this dynamic: the rising power’s growing entitlement, sense of its importance, and demand for greater say and sway, on the one hand, and the fear, insecurity, and determination to defend the status quo this engenders in the established power, on the other.

In the case about which he wrote in the fifth century B.C., Athens had emerged over a half century as a steeple of civilization, yielding advances in philosophy, history, drama, architecture, democracy, and naval prowess. This shocked Sparta, which for a century had been the leading land power on the Peloponnese peninsula. As Thucydides saw it, Athens’s position was understandable. As its clout grew, so too did its self-confidence, its consciousness of past injustices, its sensitivity to instances of disrespect, and its insistence that previous arrangements be revised to reflect new realities of power. It was also natural, Thucydides explained, that Sparta interpreted the Athenian posture as unreasonable, ungrateful, and threatening to the system it had established—and within which Athens had flourished.