James Holmes

Beware the “Thucydides Trap” Trap

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James Holmes

Beware the “Thucydides Trap” Trap

Why the U.S. and China aren’t necessarily Athens and Sparta or Britain and Germany before WWI.

Professor Graham Allison of the Kennedy School at Harvard commonly warns the United States and China not to fall into the "Thucydides Trap.” This trap, he opines, yawns wide because of "the dangers two parties face when a rising power rivals a ruling power — as Athens did in 5th century BC and Germany did at the end of the 19th century. Most such challenges have ended in war. Peaceful cases required huge adjustments in the attitudes and actions of the governments and the societies of both countries involved."

Allison is referring to Thucydides' famous statement that it was the rise of Athenian power and the fear it inspired in Sparta that constituted the true cause of the Peloponnesian War. I have my doubts about this rather mechanical reading of Thucydides' history, and about whether the father of history meant to propound a general rule of international affairs. Straight-line projections often say something important. They help reveal the context within which power politics unfolds. But human decisions, actions, and interactions matter as much as any measure of national power or any trend the observer may chart — often more so.

The Greek precedent maps to contemporary circumstances imperfectly at best. Indeed, this is one historical analogy that's instructive precisely because of the differences it exposes. Simple realities of power were at work in the Greek world, but Sparta was no America. Far from being an established custodian of the regional order, the Spartans were loath to exercise leadership. That's different from a Great Britain or an America at its zenith, a global marine power jealous of its standing.

The Spartans' reticence frustrated their allies while opening the door for Athens to vie for regional supremacy. It was the Athenians who led the effort to mop up the remnants of the Persian incursion following such apocalyptic battles as Thermopylae, Salamis, and Plataea. They rode their success to leadership first of a league of city-states, and ultimately of a nautical empire scattered across much of the Mediterranean world. That sounds more like Britain or the United States.

But it was the character of Athens' rise, not the mere fact of its rise, that helped set the Peloponnesian War in motion. Hubris — overweening pride that brings forth divine punishment — is a central theme in Greek history and literature. The Athenians contracted a bad case of it while rolling back the Persians and founding their empire. Half a century after the fact, as Thucydides tells it, Athenian emissaries were still regaling anyone who would listen about the city's part in defeating Persia. Meanwhile, their consensual league of states mutated into a tyranny. Small wonder the Spartans fretted over Athens' rise. Economic and naval might joined to such bombast must have looked menacing indeed.

So how rising and established states conduct themselves matters. It's not just about power. Now consider the modern case Professor Allison cites, that of Imperial Germany and Great Britain a century ago. Why single out Anglo-German antagonism when two other sea powers, the United States and Imperial Japan, were on the rise at the same time?

According to the Thucydides Trap metaphor, Britain should have faced the prospect of conflict with not one but three powers on the make. Yet the British cut deals with Tokyo and Washington that let the Royal Navy draw down its North American and Far Eastern stations and pull back to European waters. The relative dearth of Anglo-American and Anglo-Japanese enmity before World War I works against the Thucydides Trap thesis. There's no substitute for probing the strategic context in full.

Ferreting out other factors reveals, for instance, that Britain's overriding concern was Germany, its mercurial Kaiser, and its High Seas Fleet. Like classical Athens, Germany combined capability with worrisome intent. And its fleet was close by, just across the North Sea from the British Isles.

The United States and Japan, by contrast, were faraway powers. Neither was especially hostile. Hypothetically speaking, they could menace British interests. Overseas interests, however, took a back seat to homeland defense. Accommodating Washington and Tokyo thus seemed like a natural choice for London by the antebellum years. Nor did Japan or America have to make the "huge adjustments" of which Allison writes to stave off conflict with Britain. Royal Navy squadrons steamed away, leaving the U.S. and Imperial Japanese Navies ascendant in their home regions. That suited the regional contenders just fine.

Similarly, survey today's strategic landscape. The BRICS countries — Brazil, Russia, India, China, South Africa — are making their ascent to regional if not world power. The Thucydides Trap suggests that dark days lie ahead for them and for America. But how likely is conflict between the United States and Brazil, India, South Africa, or even a prickly Russia? Not very, methinks.

That leaves China. The trend lines in East Asia point to competition or even conflict. But trends are not fate. How events unfold will rest mainly with decisionmakers in Washington, Beijing, and other regional stakeholders. That — not a simple parable of rise and decline — is the lesson from Thucydides.