What is the significance of the Biden-Xi summit on Wednesday? In one line: two adult leaders engaging in serious, candid, private conversation about the most consequential bilateral relationship in the world.

As they did a year ago in Bali on the sidelines of the G20 summit, they will further clarify both leaders’ understanding of two contradictory but nonetheless inescapable facts. First, the US and China will be the fiercest rivals history has ever seen. Second, each nation’s very survival requires a degree of cooperation from the other.

Both know in their bones that an unlimited war between these two great powers would be catastrophic for both. They have internalized the profound truth stated most succinctly by President Reagan: a nuclear war cannot be won (since at the end of it one’s own country will have been destroyed)—and the big therefore that follows: must never be fought. Both understand that avoiding war requires serious, candid conversation between themselves, their trusted assistants, and their governments to prevent misunderstandings, miscalculations, and the impact of accidents or third-party incidents from dragging them into a war neither nation wants.

At the same time, Biden has no illusions about Xi’s ambitions—or about ours. In Xi’s grand narrative, China is inexorably rising and the US irreversibly declining. Washington observers eager to embrace the recently fashionable narrative that China has peaked should examine the numbers. While press headlines shout about positive signs in the US economy and negative headwinds faced by China, brute facts are hard to ignore.

Absent a sharp divergence from current trends, when 2023 ends in two months, the facts will show that China’s economy grew twice as fast as the US. Similarly, as the US has become more entangled in supporting Ukraine’s war against Putin’s aggression and Israel’s response to Hamas’ terrorist attack on October 7, China has joined most of the rest of the world in advocating for an end to the bloodshed and calling for negotiations. As China’s state-run People’s Daily put it recently: “the balance of global power is trending towards a rising east and a falling west; a rising south and a falling north.” In Xi Jinping’s words, “the more difficult the moment, the more confident we must be.”

As surely as Teddy Roosevelt led the United States into what he was certain would become an “American century,” Xi is similarly confident that the 21^st century will belong to China. He is determined to lead China past its “century of humiliation” at the hands of Western powers into a new era of Chinese greatness. Long before President Trump raised the MAGA banner, Xi had proclaimed that the time had come to make China great again: in his words, the “great rejuvenation of the Chinese nation.” He foresees China displacing the US as the predominant power in the Asia-Pacific during his reign (which he expects to last until at least 2035), and, in time, perhaps, the world.

Biden and his national security team know that the US has been the world’s leading power for the decades since World War II—and are determined that it remain so. They are proud of the international order the US has built that has allowed the world to experience an unprecedented “long peace” of 78 years and has enabled citizens in both the US and the world to enjoy greater increases in their incomes, health, and standard of living than in any similar period in recorded history. And they are determined to do all they can to ensure this continues.

Thus, in relations with China, Biden’s objective is to shape the conditions in which this rivalry between America’s democracy and China’s Party-led autocracy can play out peacefully over the decades to come—without falling into the trap that has so often ensnared Thucydidean rivals in unintended war.

About the Author 

Graham Allison is the Douglas Dillon Professor of Government at Harvard University where he has taught for five decades.  Allison is a leading analyst of national security with special interests in nuclear weapons, Russia, China, and decision-making.  Allison was the “Founding Dean” of Harvard’s John F. Kennedy School of Government, and until 2017, served as Director of its Belfer Center for Science and International Affairs which is ranked the “#1 University Affiliated Think Tank” in the world.