Interview:GrahamAllisonSees‘MutualDeterrence’StabilizingChina-U.S.Relations

Graham Allison, founding dean of the Harvard Kennedy School, speaks on Jan. 21 at the Caixin Davos CEO Luncheon in Davos, Switzerland. Photo: Yang Lü /Caixin

During the World Economic Forum Annual Meeting 2026, Graham Allison, founding dean of Harvard Kennedy School and the scholar best known for coining the term the “Thucydides Trap,” said that “the international security order that we’ve enjoyed for our entire lives is at greater risk of being overturned today than at any point previously.”

Allison urged the audience to remember three numbers: 80, 80, and 9. “If you can identify the question to which each of these is the answer, you’ll have the big picture about the international security order today,” he said at the Caixin Davos CEO Luncheon on Jan. 21.

As discussions at this year’s Davos forum swirled around U.S. President Donald Trump’s remarks suggesting potential control over Greenland, Allison noted: “If you were living in Greenland, or you were in Denmark, or you were part of NATO, there are a lot of things that you took for granted you maybe should have a second thought about.”

He stressed that the international security order that people have grown accustomed to “is not a natural fact, but a largely unrecognized and almost unbelievable accomplishment which reflects intelligent, persistent, hard work by successive Democratic and Republican administrations over almost eight decades.”

Looking back, Allison observed, “Last September, we celebrated 80 years without a great power war and without the use of nuclear weapons in war.” Over the past millennium, he noted, “every generation or two there’s been a great power war.” The current period, he argued, represents “the longest period without a war between great powers since the Roman Empire,” yet it is “very unnatural, very fragile, and not likely to be sustained.”

Allison emphasized that the international security order that was constructed in the aftermath of World War II “is now at greater risk of unraveling than at any point in the past eighty years.”

He explained that the economic dimension of this postwar order included institutions such as the World Bank, the International Monetary Fund, and the General Agreement on Tariffs and Trade, all designed to structure economic relations. On the security side, it included NATO, the U.S.-Japan security treaty, and the U.S. alliance with South Korea, among others.

The second “80” refers to the number of years since nuclear weapons were last used in war. Again, Allison stressed, this outcome was not accidental but rather “a remarkable achievement.” It was made possible largely through the Nuclear Non-Proliferation Treaty, extended deterrence, secure alliances and numerous other mechanisms.

The third number, “9,” refers to how many states currently possess nuclear arsenals. “Nuclear weapons are an 80-year-old technology. North Korea has a nuclear arsenal. So why not Japan? Why not South Korea? Or Switzerland, or Canada?” Allison said. “The answer is because the non-proliferation regime was created out of America’s and the Soviet Union’s brush with nuclear Armageddon during the Cuban Missile Crisis. That regime is a fragile institution that must be maintained constantly and is currently at risk of unravelling.”

Thucydides trap

In discussing the potential disintegration of this order, Allison referenced his November 2025 Foreign Affairs article titled The End of the Longest Peace?

During his remarks, Allison also revisited arguments from his book “Destined for War,” describing U.S.-China relations as a classic Thucydidean rivalry: a rapidly rising power confronting a major ruling power. “The discombobulation caused by a rapid shift in the seesaw of power most often — and tragically — ends in war,” he said, “as tragic as it would be for both countries.”

Beyond the classical example of Athens and Sparta, Allison suggested a more modern analogy: “If you want a more relevant example as we think about U.S.-China relations today, go back and study the period between 1910 and 1914.”

At that time, Germany was rising while the British Empire dominated the global order. “People in Great Britain were feeling uneasy as they saw Germany challenging its position. Germany felt Britain was trying to hold it down — preventing it from having colonies and not allowing it opportunities to become what it wanted to be.”

Yet neither side necessarily wanted war. “Actually, Germany and Great Britain did not want a war. The two leaders — the king and Kaiser Wilhelm — were cousins and went on vacations together.”

However, “something as bizarre as the assassination of an archduke in Sarajevo became the spark that ignited a fire that within five weeks had engulfed all the nations of Europe in war — a war that became so destructive that historians had to create a new category of war: World War.”

Applying this framework to U.S.-China relations, Allison warned that “the best candidate for such a spark that could create a fire is Taiwan.

Despite these risks, Allison noted that the past year in U.S.-China relations, though turbulent — including unprecedented 145% tariffs and China’s tightening of rare earth magnet supply chains — eventually led to a truce.

When President Xi Jinping and U.S. President Donald Trump met, “they both expressed their eagerness to create a new and different relationship — a more positive and constructive relationship.” The two leaders have set an agenda for 2026, beginning with a summit in April when Trump is expected to visit Beijing, followed by Xi’s potential visit to the United States later in the year, possibly in November or December. Additional meetings may also take place on the sidelines of the G20 in Florida or the APEC meeting in Shenzhen.

“If I were betting looking forward, I’d say the outcome is slightly more likely to be positive — though there are many ways things can get off track. One day it’s one thing; the next day it’s another.”

Still, Allison said he sees some “silver linings.” “I can see the outline of what President Xi and President Trump might announce in April or May — a new rapprochement or even a new partnership, perhaps a partnership for peace and prosperity. That’s the hope I have looking ahead.”

Silver lining

On Jan. 22 local time, at a public World Economic Forum session on the future direction of U.S.–China relations, Allison again laid out the structure of Thucydides Trap between the United States and China.

He said that “a rapidly rising China that seriously threatens America’s colossal ruling position.” “This rapid shift in the see-saw will magnify misunderstandings, multiply miscalculations, and amplify the probability of incidents or accidents that would otherwise be inconsequential.” He stressed that “these are structural realities of the relationship” that “Xi and Trump have to grapple with.”

Allison also stated that a relatively promising element in this context is that Trump understands a hot war between the U.S. and China must be avoided: “the promising thing in this context is that Trump understands war is terrible. Again, that’s a good thing for a president to understand.”

He added that “Trump understands that nuclear war, it’s really, really, really bad, and that’s also a good thing for a president to understand. So that is the dynamic in a world in which there are two parties who have no alternative to coexistence than co-destruction. And I’d say that’s a foundation for a more positive stage in the relationship.”

Looking back at the U.S.-China trajectory since Trump returned to office — renewed trade confrontation to a temporary truce — Allison described it as Trump trying to bully someone and discovering that China was prepared.

“It turned out that Xi was not willing to be bullied by Trump,” he said, adding that “Xi tightened control of the supply chain for rare earth products, threatening the entire American economy.” Afterward, “the two parties recognized that they’re entangled in a way such that they’re going to have to find a way to work together,” which “in other realms of strategy would be called mutual deterrence.”

He described the new dynamic between the U.S. and China as “a condition of mutual deterrence in which each party can do significant harm to each other. That, Allison concluded, “has a stabilizing effect on the relationship overall.”

“Remember, it is because each are threatening to do something pretty horrible to the other. So it’s not a desirable state to be in,” he said.

However, he pointed that’s it still better than a military confrontation. It “certainly reflects more realism in Washington about China as a full-spectrum peer competitor,” he said.

When addressing criticism that Trump tends to retreat at key moments — often summarized as TACO (Trump always chickens out) — Allison said: “Trump doesn’t always chicken out.” He argued that “He only chickens out when confronting a stone wall or an equally serious opponent who can do at least as much damage to him as he can do to them.”

Taiwan as a flashpoint

Allison said that beyond understanding at the leader-to-leader level — understanding each other’s motivations and the constraints of the rivalry — additional channels for communication between the U.S. and China are needed.

He argued that “there need to be at least one or two levels of continuous, candid, private conversations about potential misunderstandings in the relationship. Even at their lowest point during the Cold War, the U.S. and Soviet Union maintained a hotline for resolving the most dangerous disputes.”

He then contrasted two Taiwan-related episodes. He said that “if you look at the difference between a Pelosi visit to Taiwan, which was a reckless action invited by Speaker Pelosi that produced a year of very bad relations between the U.S. and China” and an alternative example — “the transit arrangement for Lai” — the difference is clear.

In the latter case, he said, “the two governments privately talked in advance about how this could be disturbing to the two big guys,” understanding that “for them, Lai and Taiwan are bright red lines.”

“That’s called diplomacy,” he concluded.

In response to a Caixin question on whether Beijing and Washington could reach some form of tacit diplomatic understanding on Taiwan during the remaining three years of Trump’s presidency, Allison said that at least one thing is certain so far: “Trump is extremely unpredictable. When we see someone acting so contrary to what we’ve come to believe has created the international order that gave us these blessings, we’re confounded.”

Secondly, he said that “both he and Xi appreciate that Taiwan is a potential flashpoint between the U.S. and China,” and that this “was a subject of conversation in the first term about which they had some understanding.”

Allison said he could imagine further formalization of diplomacy between Beijing and Washington on the Taiwan question before the end of Trump’s second term: “I could even see a fourth U.S.-China communique that would produce the basis for a larger agreement in the future.” “Although,” he added, “any outcome would depend on there being a surge of strategic imagination from both sides.”

Contact editor Lu Zhenhua (zhenhualu@caixin.com)