“Thucydides’ Trap” has become a familiar term in scholarly and even popular discourse on Sino-American relations. It points to the ancient rivalry between Athens and Sparta as an analogy for contemporary relations between China and the United States. This analogy warns about the increased danger of war when a rising power catches up to an established power. This essay raises concerns about (mis)application of historical analogy, selection bias, measurement problems, underspecified causal mechanisms, and so on that undermine the validity of the diagnosis and prognosis inspired by this analogy and other similar works. My objection to this genre of scholarship does not exclude the possibility that China and the U.S. can have a serious conflict. I only argue that this conflict can stem from sources other than any power shift between them or in addition to such a shift. By overlooking other plausible factors that can contribute to war occurrence, a monocausal explanation such as Thucydides’ Trap obscures rather than clarifies this phenomenon. Because it lends itself to a sensationalist, even alarmist, characterization of a rising China and a declining U.S. (when the latter in fact continues to enjoy important enduring advantages over the former), this perspective can abet views and feelings that engender self-fulfilling prophecy. Finally, as with other structural theories of interstate relations, Thucydides’ Trap and other similar formulations like power-transition theory tend to give short shrift to human agency, including people’s ability to learn from the past and therefore to escape from the mistakes of their predecessors.