On a Tuesday evening in March, veterans of America’s war in Afghanistan are sitting at an outdoor patio bar in Washington, DC. The presence on the menu of steak tartare, lobster ceviche and truffled chips is the only clue that this is a rarefied hotel in Georgetown, one of the capital’s most expensive neighbourhoods. The atmosphere otherwise is a fug of “fucks” and spent hopes.

One of the vets says he was shot in the hamstring (“the ass”, his friends correct him with glee). Another lost his leg to an improvised explosive device in Kandahar in 2012. He recovered in the nearby Walter Reed National Military Medical Center.

One day during treatment, he snuck out of the facility to a bar. He was just knocking back his first drink when a young couple he didn’t know asked him about his injury. “I lost my leg in Afghanistan five weeks ago,” he answered.

They were shocked: “Do we still have troops in Afghanistan?”

Almost a decade later, US troops are just beginning their final pullout from the country. They were first sent by President George W Bush in 2001, a month after the September 11 attacks; he called it “civilisation’s fight” and went on to topple the Taliban. His successor, Barack Obama, ordered a troop surge which took US forces there above 100,000 and he spoke in 2012 of Americans in Afghanistan answering “the call to defend their fellow citizens and uphold human dignity”.

But the US experience tells a harsher story. So far, the undertaking has cost it an estimated $2tn and 2,448 lives. More than 20,700 Americans have been wounded, with hundreds losing limbs. Research suggests that about a fifth of the 775,000 US troops who have served in Afghanistan, some on more than five tours, suffer from depression and post-traumatic stress disorder. More than 45,000 veterans or service members have died by suicide since 2013. Most US veterans now say the wars in Iraq and Afghanistan were not worth fighting.

A platoon posted in Kunar province in 2008 dig earth for sandbags to reinforce a bunker

Last month, US president Joe Biden announced that this chapter in American history would finally close. The 2,500 remaining US troops are to be withdrawn by September 11 — the 20th anniversary of the 2001 attacks — with no sign of winning. As well as its impact on the military, the war has shaken something deep in America’s sense of itself. A shift seen across the political spectrum has begun to probe the global role of the US and even the idea of American exceptionalism, a notion that the country is a unique force for good in the world.

Adherents of America’s moral exceptionalism tend to reach back to the US’s creation story — in 1780, future president Thomas Jefferson said America was the “empire of liberty” — and the creed has had profound political consequences for wartime and peacetime alike. The US shaped multilateral institutions such as the UN, Nato and the international monetary and financial system that emerged after the second world war.

But the superpower has also tended to absent itself from multilateral pacts when it has not shaped the rules or risks coming under unfavourable scrutiny — whether it’s the International Criminal Court in The Hague or a series of international agreements about the rights of women, children and organised labour; some limits on torture and cluster bombs; even access to the moon. In the postwar period, the idea has been used to justify military intervention, coups and covert activity everywhere from Greece and Vietnam to Nicaragua and Iraq.

The unlikely standard-bearer for a less exceptionalist US was Donald Trump, who said in 2015 that the notion of American exceptionalism was “insulting” to the world and that he “never liked the term”. It was Trump who, as president, struck a deal with the Taliban in 2020 and promised to withdraw all US troops from Afghanistan in 2021, just a few months ahead of Biden’s eventual date.

Now a new wave of academics, veterans and policy experts is trying to upend the consensus on American exceptionalism, playing insurgent David to the foreign policy establishment’s Goliath. Some aim not only to question the militarisation of US foreign policy, but also its moral underpinnings and claims that the world requires America as its leader. One new anti-exceptionalist think-tank, the Quincy Institute, is even uniting opposite points on the political compass, from George Soros to a Koch brother.

The US has questioned its role in the world before, not least as it grappled with whether to enter the second world war and in the wake of Vietnam. Yet if this anti-exceptionalism gains the intellectual upper hand as geopolitical dynamics shift and the US enters a new competition with China, it will entirely change how America relates to the world and the claims it makes on the 21st century. Will the US really countenance any vision of global geopolitics where it isn’t sole superpower?

There are signs that senior figures within the Biden administration are sympathetic to a re-evaluation of the primacy of American exceptionalism. In an interview with the Financial Times, national security adviser Jake Sullivan says he has “not specifically heard” the president use the term and that he doesn’t know what Biden would say if asked if he was an “American exceptionalist”.

He says Biden is more concerned with “American purpose, American capacity . . . It hasn’t been about wording. It’s been about underlying propositions and principles guiding our foreign policy.” Sullivan himself has grappled with the phrase, saying some definitions of it were associated with deep problems and dangers, and has sought to sketch out a more limited vision.

In the DC bar, the two veterans count themselves as patriots and don’t regret their military service — indeed, they still work for the US government in the region. (They requested anonymity to speak freely.) But they no longer accept moral or strategic arguments for America’s overseas military operations and reject what they see as the continuation of an imperialist, exceptionalist foreign policy.

“I was raised with the belief that we’re always the good guys on the side of right,” says the first man, who now rues America’s expansive network of more than 750 overseas military bases. “I don’t believe the national bedtime story any more.”

For many of its domestic advocates, American exceptionalism offers the comforting notion not only that America is globally best — by dint of wealth, power, constitution, ethos, geography or any other advantage, whether natural or attained — but also morally justified in this status. Presidents and political figures throughout its history have eagerly promoted America as a singular example to the world.

To Abraham Lincoln, invoking the country’s 1775-83 revolutionary struggle against the British, America “held out a great promise to all the people of the world to all time to come”. On the eve of the 1861-65 civil war, fought over the future of slavery, Americans were God’s “almost chosen people”, he said. In the 19th century, the idea that the US was destined to spread its dominion led to first domestic and then overseas expansionism. To Jay Lovestone, a US communist, American exceptionalism meant US capitalism was so advanced it would never conform to Marxist expectations for revolution.

American exceptionalism has been a capacious concept. Some have used it to justify the isolationism that followed the first world war, others its triumphant intervention in the second. The cold war gave rise to a new interpretation, the pursuit of an enduring transatlantic architecture that would further US hegemony as the world’s only superpower.

More recent US presidents have called on American exceptionalism almost as proof of patriotism. For Bill Clinton, the US was “the indispensable nation”. For Obama, it was the belief that America was built on “a core set of values” urging it on to do better. Since 2012, American exceptionalism has formed an official plank in the Republican platform, prophesying “another American Century”.

For the most ardent believers, one image has developed staying power. In 1961, shortly before he became president, John F Kennedy told Massachusetts lawmakers that, “We shall be as a city upon a hill — the eyes of all people are upon us.” Ronald Reagan too spoke frequently of 1980s America as a “shining city on a hill”. The reference is to a 1630 sermon by English Puritan John Winthrop, who emigrated from England to found the Massachusetts Bay Colony that year — a community he wanted to be a model of Christian charity and which he regarded as divinely inspired.

The retired Princeton historian Daniel Rodgers wrote a 2018 book about Winthrop’s sermon. He argues that the idea that the US has always acted benignly — inherent to American exceptionalism — is a “dangerous myth”. “The idea that there’s a kind of timeless God-given power to the Americans simply gets in the way of really careful examination of what a very powerful nation in the world can and should be doing,” he says. The notion that America was an exception to the rules that govern every other nation’s history has led to blind spots, he adds: “America has had times of great moral lapse.”

US defence spending compared to 10 major countries combined in 2019

Critics have plenty of ammunition, pointing to cold-war operations spanning assassination plots, destabilising regime changes or outright conflict in Korea, Syria, Egypt, Iran, Guatemala, Chile, Indonesia, Cuba and many more. The US is an exceptional power in the way it has deployed its wealth and largesse, but also its force: it is the only country to have detonated nuclear weapons in wartime. In the 1970s, congressional investigations exposed a series of covert actions overseas by the CIA to undermine governments. In the wake of the September 11 attacks and invasion of Afghanistan, the US established a global network of torture “black sites”. It is in no position to lecture others, argue some.

In an email, author Suzy Hansen, a critic of America’s foreign policy, says: “The habit of militarised response, the presumption that the country can act with impunity and, frankly, the ease with which the military kills people abroad . . . has also infected the entire American project and Americans’ psychology.”

The shining, exceptional city on the hill is not all its promoters claim for it. After Winthrop arrived in America, he went on to condemn democracy as “the meanest and worst of all forms of government”.

There aren’t many causes that can unite the liberal hedge-funder George Soros and one of the conservative Koch brothers, billionaire industrialists who built a network of Republican donors. But in 2019, both Soros’s Open Society Foundations and the Charles Koch Foundation gave $500,000 apiece for the founding of the Quincy Institute for Responsible Statecraft. Events at the institute have questioned, among other things, whether exceptionalism should still be seen as “an untouchable third rail in US politics”.

It is named after John Quincy Adams, the sixth US president, who warned as secretary of state in 1821 that America risked becoming “dictatress of the world” if it chose force over liberty. America, Quincy argued, “goes not abroad, in search of monsters to destroy” and should be a “well-wisher to the freedom and independence of all”.

Lora Lumpe, an expert on what she calls US “hyper-militarisation”, was working for the Open Society Foundations when she reached out to the Charles Koch Institute to collaborate in a bid to challenge the militarisation of US foreign policy. “We both came at it from our corners, which had kind of demonised the other,” she says. She has since joined the Quincy Institute as chief executive.

The institute has put its campaign to withdraw from Afghanistan at the forefront of its recent efforts. US media now regularly features Quincy’s viewpoints; the institute says it was featured in 196 op-eds and features last year, in publications ranging from The New York Times to Teen Vogue.

Quincy may have time on its side. In 2011, only 8 per cent of Americans believed “there are other countries that are better than the US”, according to the Pew Research Center. But that proportion rose to 21 per cent in 2019, says Pew, and it is even higher — 36 per cent — among 18 to 29-year-olds (up from 12 per cent in 2011). For young voters on the left, it rises to 47 per cent. (The two surveys were conducted by different methods so might not be directly comparable.)

The recent mood found echoes at the top too, even if Trump made an unlikely bedfellow for some sceptics of American exceptionalism. Sam Long, 33, arrived in Afghanistan in 2013 as a Marine Corps captain with a romanticised view of the counterinsurgency work he thought his team would be doing. But he grew to despair that Washington’s foreign policy elite was constantly pushing to extend the war, a misgiving that put him uncomfortably close to Trump, who blamed “stupid leaders” for prolonging it.

Of Trump, the Democrat-leaning Long says: “It pains me that that guy, with all his flaws, with all his dishonesty, with all his narcissism and his total lack of worldliness and his total lack of an understanding of other places, was the one who said: What the hell are we doing? This is stupid.”

One Quincy piece was written by another soldier turned anti-exceptionalist: former Marine Corps first lieutenant Gil Barndollar. Before he arrived in Afghanistan for his second tour in 2013, serving in Helmand province after meeting Long during training, he had been an intern in 2004 at the American Enterprise Institute, a hawkish think-tank he describes as “the beating heart” of the push for the 2003 Iraq war.

Barndollar, who is now 39, had believed in “a more or less crusading American exceptionalism” but grew disaffected. He sees himself as a patriot and still feels it was “paradoxically the most meaningful thing” he has ever done, but came to view US nation-building overseas as a folly and discerned in the US a deep-seated creation myth that had put it on a “pernicious pedestal”.

“You should talk about probably just how lucky and how fragile the American experiment is — it’s a lot more persuasive than some idea of this country leading the world,” says Barndollar, who in 2019, two years after leaving the Marines, became a senior fellow at Defense Priorities, a conservative think-tank that argues for the “more judicious” use of the American military.

Quincy has also attracted serving congresspeople. Progressive Democratic congressman Ro Khanna, who represents part of San Francisco, has been a speaker at its events and argues against military interventions, although he still sees himself as an American exceptionalist — on domestic matters, at least. “America is a unique experiment . . . becoming the first major multiracial, multi-ethnic democracy in the world,” he says, looking back not to the arrival of the Puritans or the founding fathers whose liberty applied to a select group of men, but to an 1869 speech from Frederick Douglass about the composite nation. “[Douglass] really paints a vision of America as a nation of nations — a universal nation,” Khanna says.

In 2019, potential Quincy collaborators held a two-day retreat to bash out whether their contrasting beliefs really could meld. According to previously unpublished minutes of the retreat, Andrew Bacevich, a conservative historian and former self-described cold-war warrior, said American ambitions had failed to diminish after the “emergency” of the cold war ended, arguing that America instead “became the sole superpower and used its enormous power even where the national interest was not at stake”.

Bacevich had another motive too: his son was killed in Iraq in 2007. “His death haunts me and I want to prevent it happening to other Americans,” he said. Bacevich is now the institute’s president.

But America has skirted such moments before. Bacevich, who served in the Vietnam war, believes its lessons have been insufficiently learnt. “Both Vietnam and Iraq remain bizarrely undigested,” he has written. “Both conflicts left behind a poisonous legacy of unrest, rancour and bitterness” and offer a better yardstick for US involvement in wars than its lauded contribution to the second world war, he noted.

The Vietnam war, in which more than 58,000 US troops died, galvanised powerful domestic protest movements and exposed social cleavages. But so-called Vietnam syndrome — the subsequent disinclination for war accompanied by revelations about the expansive covert role of the CIA — wore off in the 1980s when Reagan set about rebuilding the military and focused on fears of a nuclear arms race and the possibilities of war in space.

In 1991, the US was back to war in the Gulf, with President George HW Bush declaring: “The ghosts of Vietnam have been laid to rest beneath the sands of the Arabian Desert.” The September 11 attacks galvanised a new generation of volunteers — and then came Afghanistan.

In ordering the final withdrawal of US troops from Afghanistan, Joe Biden has surprised many — overriding military advice and the received wisdom of Washington’s foreign policy establishment.

Should this be taken as an anti-exceptionalist statement? Biden’s administration has been at pains to show it wants a less hawkish US foreign policy — explicitly rejecting regime-change policies and raising expectations it will downsize the country’s colossal defence spending and overseas military presence. But it still channels the language and ambition of American exceptionalism. In his address to Congress last week, Biden described America as “the most unique idea in history” and said: “We have, without hyperbole, the greatest fighting force in the history of the world.”

Jake Sullivan, the president’s national security adviser, says his own thinking “rhymes with” the way Biden has thought and talked about foreign policy for a long time. “When it comes to the question of the ‘superpower’ . . . I think the United States does have a distinct role to play catalysing and mobilising collective action to solve big problems,” he says. If the US is absent and no one else has “the will or the purpose”, you get “drift and inaction”.

But the term “American exceptionalism”, says Sullivan, “is not itself animating the administration, because we take our lead from the president, who has provided a view of the role of the United States in the world that is distinctly his”.

Sullivan describes the president as optimistic, confident and determined that an “enlightened self-interest” which serves the US and delivers positive outcomes for the larger common interest should be at the core of US foreign policy. Biden’s optimism, says Sullivan, “is rooted in part in a humility that says America will stumble and fall and get knocked down on the mat, but what makes our country capable of great things is that we get back up again, and we learn from our mistakes and we self-correct and we move forward.” Biden, however, also wants to “win the 21st century”.

The context of this assertive — yet more fragile — tone is the rise of China and the prospect of America’s relative decline. The shadow that China could one day dislodge the US threatens many ideas 21st-century Americans take for granted about themselves. Biden has publicly pitched a “battle” between democracies and autocracies.

Four years of an isolationist Trump presidency filled with U-turns have undermined US standing among its traditional allies and partners, and the US has faced domestic protests over gun crime, racism, sexism, healthcare and even election results. Realising Biden’s mantra as president — that the US must lead “not just by the example of our power, but the power of our example” — will be an uphill climb.

Even the history of that example is now in doubt. Linda Thomas-Greenfield, Biden’s ambassador to the UN, said last month: “I have seen for myself how the original sin of slavery weaved white supremacy into our founding documents and principles.” Secretary of state Antony Blinken has said he wants to “balance humility with confidence” — a position he has taken partly to deal with criticism from foreign diplomats who highlight US strife at home. But he is no less determined that America should lead the world and is committed to democracy and human rights promotion beyond US borders.

The president has made clear his focus is delivering for the American people at home. But in late March, at his first press conference in office, he said China’s “overall goal” was to become the wealthiest and most powerful country in the world. “That’s not going to happen on my watch,” he said, invoking the language of superpower rivalries. “Because the United States are going to continue to grow and expand.”

Though Lumpe and the Quincy Institute are now satisfied when it comes to Afghanistan policy, this is the kind of language that alarms her. “Despite [Biden’s] good decision on Afghanistan, American exceptionalism is alive and well,” she says following the drawdown announcement, arguing that the default position of both parties in Congress is to believe that American power is limitless. “If China sent special operations forces or used lethal drone strikes in a half-dozen African or Asian countries to combat potential anti-Chinese terrorism, Washington would lose its mind. That’s American exceptionalism.”

Barndollar suggests that while the fashion in Washington may be turning against explicit support for US military interventions and what he says is a propensity for “spreading American blessings with the bayonet”, a fixation with American primacy and an unwillingness to acknowledge the limits of American power still affect foreign policy professionals on both the left and the right. Quincy and other organisations like it “have carved themselves a spot in the conversation but they’re still fighting uphill”, he says, and are in a clear minority. Anti-exceptionalist conservatives working on US foreign policy “would all fit into half an Irish bar”, he laughs.

Will Biden genuinely usher in a humbler role for the US? “It’s still an open question, but it seems he doesn’t really want to be a foreign-policy president, and that’s good,” says Barndollar.

Mike Gnoffo, a Marine Corps sergeant who served with Sam Long, had been “ecstatic” to deploy to Afghanistan in 2013 after joining the reserves eight years earlier at 19. Combat gave him the test — and sense of purpose and belonging — he had been seeking. “Violence had come to feel like an obligation,” he wrote in 2018, a year after leaving the Marines.

Gnoffo, who now works in the sports industry, argues for the necessity of US global leadership, which he sees as bound up with the possibilities of progress, but has grown disappointed by what he sees as the role of the US perpetuating war, including the “useless” fight in Afghanistan. “The idea that we’ve been walking around with a big stick for 20 years now and breaking shit — really, what has it built, other than a tremendous pile of debt? Death too,” Gnoffo says. “Maybe American exceptionalism is the reality that we can spend that money and it doesn’t bankrupt us.”

Katrina Manson is the FT’s US foreign policy and defence correspondent

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