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Sleepwalking into Thucydides's Trap: The Perils of US Hegemony


Sleepwalking into Thucydides’s Trap: The Perils of US Hegemony
Leo Keay*

The threat of great power warfare is the defining geopolitical question of this age. The 2018 National Defence Strategy (NDS) describes the re-emergence of long-term strategic competition with revisionist great powers as “the central challenge to U.S. prosperity and security”.[1]

China is America’s chief competitor; seeking to rectify its “century of humiliation”, Beijing aspires to regional influence and power across East Asia. Its growing military capabilities, especially its anti-access/area denial technologies, are intended to achieve strategic dominance in the South China Sea. Meanwhile, it seeks geo-economic influence over the region (and beyond) by becoming the leading provider of infrastructural investment and advanced industrial products to its neighbours.[2]

The most sophisticated analysis of this issue consists of Graham T. Allison’s notion of the “Thucydides’s trap”. Drawing on the Greek historian’s maxim that “it was the rise of Athens and the fear that this instilled in Sparta that made war inevitable”, Allison contends that the growth of a rising power’s capabilities relative to those of a ruling power greatly increases the probability of war. This occurs for two reasons: “rising power syndrome”, whereby the ascending polity exhibits a hubristic sense of self-importance and aggression; and “ruling power syndrome”, whereby the established power suffers from a paranoid sense of insecurity at its own decline.[3]

Nevertheless, Allison does believe that Thucydides’s trap can be avoided. In four out of his sixteen historical case studies, ruling powers did peacefully accommodate rising powers.

One notable example was the “Great Rapprochement” between Britain and the US at the end of the nineteenth-century.[4] Britain conceded supremacy in the Western hemisphere to the US because it faced a more direct threat to its imperial possessions and naval supremacy from Germany. Britain therefore sacrificed its vested interests in one domain to preserve its vital interests in another.[5]

Allison recommends that Washington pursue a similar course, prioritising the avoidance of nuclear war over its strategic and economic primacy in the Pacific.[6]

While Professor Allison’s effort to draw lessons from history is praiseworthy, his analysis of the “Great Rapprochement” misses an important point. Unlike twenty-first century America, nineteenth-century Britain was not a hegemon. Despite its naval superiority, Britain was never a significant land power in continental Europe.[7] It was instead a leading member of a multipolar great power system. For this reason, London was used to making significant concessions to other states in order to protect its vital interests. In the 1880s, for instance, it sacrificed zones of informal influence in West Africa to France and East Africa to Germany, in order to safeguard its core possessions of Egypt and South Africa. Accordingly, the “Great Rapprochement” was yet another pragmatic trade-off which came naturally to British statesmen.

The US’s position today is different. Since the end of the Cold War it has enjoyed global hegemony, underpinned by its unipolar military capacity and its extensive alliance network. Consequently, Washington is prone to regard any accommodation of Beijing’s ambitions as a unilateral retreat rather than a necessary compromise.

President Trump’s National Security Strategy (NSS) exemplifies this outlook.[8]China’s ambitions are described as “antithetical to U.S. values and interests”. Both states are engaged in “a geopolitical competition between free and repressive visions of world order”,[9] whereby China seeks to “displace the United States in the Indo-Pacific region”.[10]

Washington’s alliance commitments further intensify its rivalry with Beijing. Any failure to side with partners such as Japan and the Philippines in a confrontation with China would weaken the credibility of America’s security guarantees. The NSS therefore calls for “sustained U.S. leadership” against China, providing a “collective response that upholds a regional order respectful of sovereignty and independence”.[11] America, therefore, appears to be suffering from an acute case of “ruling power syndrome”: the stakes of hegemony are so high that any significant concession to Beijing would irrevocably compromise Washington’s position.

This is not a unique situation, unipolarity led Napoleon to declare war against Russia in 1812. After coercing all other powers to participate in the continental blockade against Britain, he could not tolerate Russia’s refusal to cooperate. Despite his personal friendship with Tsar Alexander, Napoleon could only see Russian policy in hostile terms, concluding in 1811 that “war will come about, though I don’t want it, neither does he, and though it is equally against the interests of France and of Russia. I have seen this happen so often before”.[12]

Rigid alliance structures also magnify the risks of great power conflict. On the eve of the First World War, Europe was divided between the “Dual Alliance” of Germany and Austria-Hungary, and the “Triple Entente” of France, Russia and Great Britain. It was the unshakeable nature of each bloc’s security commitments that transformed Austria-Hungary’s invasion of Serbia into a global military conflict.

The only way to avoid future conflagrations is to adopt an attitude of radical humility. America’s leaders must accept that the tectonic shifts of geopolitical power cannot be reversed, only managed so as to minimise friction. This is more profound than the distinction between vital and vested interests suggested by Allison. It requires the ruling power to fundamentally scale down its ambitions to those of a great power.

The US must cease to aspire to global hegemony, and instead aim for limited dominance. President Obama had the foresight to appreciate this. As he explained in his 2015 NSS: “America leads from a position of strength. But, this does not mean we can or should attempt to dictate the trajectory of all unfolding events around the world […] our resources and influence are not infinite”.[13]

One possible solution could be to return to the fundamentals of nineteenth-century US grand strategy, the Monroe Doctrine.

Washington’s priority should be to preserve its strategic autonomy in the Western hemisphere. Consequently, it must continue to safeguard its security in the Pacific by maintaining its military bases and honouring its alliance commitments there.

Nevertheless, Washington should ultimately be prepared to cede ascendancy in East Asia to Beijing. Chinese naval dominance within the First Island Chain should be accepted as a fait accompli. Furthermore, the US’s alliances should be defensive pacts providing limited support against unprovoked aggression, not blank cheques offering unconditional assistance.

These decisions might appear to compromise the world order that Washington has long worked to sustain. Nevertheless, the costs of losing global hegemony must be weighed against the benefits of retaining limited dominance.

Not only would the US avoid war with China, it would be better placed to secure Beijing’s cooperation over numerous issues of mutual interest, chiefly economic growth, international security and nuclear non-proliferation. The US would therefore retain immense influence over world politics, but less as a lone sheriff than a co-partner with China. Much will depend, however, on whether future American leaders embrace the wisdom of humility or yield to the arrogance of power.

* Leo Keay is a graduate in Modern History from Oxford University and a current MA applicant in International Relations.

[1] US Department of Defense, Summary of the 2018 National Defense Strategy of the United States of America, January 2018, p. 2,

[2] Aaron L. Friedberg, “Globalisation and Chinese Grand Strategy”, in Survival, Vol. 60, No. 1 (February-March 2018), p. 7-40,

[3] Graham Allison, Destined for War. Can America and China Escape Thucydides’s Trap?, Boston and New York, Houghton Mifflin Harcourt, 2017, p. 27 and 43-44.

[4] Ibid., p. 85.

[5] Graham Allison, “Can America and China Avoid Going to War in the Future?”, in Evening Standard, 13 July 2017,

[6] Graham Allison, Destined for War, cit.

[7] Muriel E. Chamberlain, Pax Britannica? British Foreign Policy, 1789-1914, London and New York, Longman, 1988, p. 7.

[8] The White House, National Security Strategy of the United States of America, December 2017, p. 25, [9] Ibid., p. 45.

[10] Ibid., p. 25.

[11] Ibid., p. 46.

[12] Napoleon to Frederick, King of Württemberg, Paris, 2 April 1811 (Corresp., xxii, 17553), in Letters of Napoleon, edited by J.M. Thompson, Oxford, Blackwell, 1934.

[13] Barack Obama’s statement on the 2015 National Security Strategy, February 2015,