What can Thucydides teach us about rising US-China tensions?

Much ink has been spilled of late about the rising tensions between the US and China. While this growing rivalry is felt in many spheres, including geographical, political and economic, perhaps nowhere is it more acutely present than the new arms race over so-called hypersonics, a class of missile that travels at Mach 5 speed or greater, and is generally impervious to existing anti-missile defenses. Tackling the emerging Chinese threat—including the threat from new technologies, like hypersonics—will require a concerted effort from the Western world, with a maximum of coordination and ingenuity, including an honest desire to prevent a military conflict if possible. Otherwise, we risk falling into what scholar Graham Allison has recently dubbed the “Thucydides’s trap,” referencing the collision course between Athens and Sparta recounted in The History of the Peloponnesian War.

Famous for his timeless insight into power politics, Thucydides notes that, beyond the many proximate issues that led Athens and Sparta into war, underlying them all, and making confrontation inevitable, were the powerful forces of uncertainty and fear. As Thucydides notes, “What made war inevitable was the growth of Athenian power and the fear which this caused in Sparta” (1:23). In a way not wholly unlike our own case of destabilization caused by an increasingly assertive China, Athens grew in might chiefly through its championing of new technological and military capability, specifically fortifications and naval power.

Providing perhaps the earliest account of what we now call “realism,” the idea that the distribution of power accounts for the relations among nations, Thucydides recounts the Athenian position as seeking military parity with Sparta, because, as the Athenians maintain, “it was only on the basis of equal strength that equal and fair discussions on the common interest could be held” (1:91).

By adopting supremacy in new military technologies—namely, fortifications and naval power—Athens had become a rival in earnest and thus threatened Sparta’s position, a development the latter found untenable. As Thucydides tells us, “[T]he point was reached when Athenian strength attained a peak plain for all to see and the Athenians began to encroach upon Sparta’s allies. It was at this point that Sparta felt the position to be no longer tolerable and decided by starting this present war to employ all her energies in attaching and, if possible, destroying the power of Athens” (1:118). By rising in strength vis-à-vis Sparta, the reigning hegemon, Athens threatened to upset the reigning balance of powers, unleashing a torrent of fear and uncertainty in Sparta about their position on the global stage and their future prospects. Such fear and uncertainty led, as Thucydides tells us, to war. “War,” as Australian historian Geoffrey Blainey notes, “is a dispute about the measurement of power.” When the variables change and the relative strength of two powers is no longer clear, war is often the consequence.

The similarities between the shifting scales of relative strength that set Athens and Sparta on a collision course for war almost two-and-a-half millennia ago and the escalating confrontation between the US and China is plain. When one further considers the challenge posed in our own case from potential Chinese superiority in a new, poorly understood, and incredibly dangerous new technology like hypersonics, the danger of a hot war is even more pronounced.

This is all the more reason that we should learn from history, including from teachers like Thucydides. What this means is that we should act now, not wait until we are locked-in to conflict. We cannot let a latent techno-military conflict with China continue to grow in stature until war or capitulation are the only options left on the table. A world order under an unreformed Chinese hegemony, which has yet to recognize the many and grievous mistakes of the Communist past and present, is untenable. A free China that plays by the rules and accommodates itself to the international order is desirable. However, until then, deflecting increasing Chinese aggression requires robust international cooperation and resolve, enough so that the relative position of the West convinces China that continued escalation is not in its interest. In this way, we can learn from the past and avoid Thucydides’s trap.