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As America’s longest war comes to a screeching halt, the post-mortem examination on what went wrong over 20 years of conflict begins.
The US Congress has already promised investigations into how the Taliban were able to seize Afghanistan so quickly and why President Joe Biden botched the withdrawal that has left thousands of Afghans rushing to flee the country.
The ultimate failures of Washington's two decades of Afghanistan efforts were overseen by four US presidents, but it is the Biden administration that now owns the crisis.
Here is a look at some of the key US figures involved in recent events.
Mr Biden is a long-time critic of the Afghanistan war who, as vice president, disagreed with Barack Obama’s 2009 decision to “surge” tens of thousands of US troops into the country.
Any attempt to prop up Afghanistan’s deeply corrupt government would merely mean “prolonging failure,” he said at the time, according to journalist Bob Woodward’s book Obama’s Wars.
Now Mr Biden has taken a career-defining gamble on what happens next in Afghanistan.
If the Taliban establish some sort of effective governance and respect hard-won gains for women and minorities, the president may be at least partially vindicated in his decision to end the war.
But if the hardliners do not meet promises to moderate, if they start killing former members of President Ashraf Ghani's government and military, or if they allow terror groups to operate with impunity, Mr Biden faces enormous backlash.
As vice president, he saw first-hand what happened after the US troop pull-out from in Iraq in 2011.
Mr Obama had to reverse the withdrawal in 2014, sending thousands of US forces back into Iraq as ISIS rampaged across the country and the national army collapsed.
Mr Biden on Wednesday insisted the Afghanistan withdrawal was always going to end in bedlam.
"We're gonna go back in hindsight and look, but the idea that somehow, there's a way to have gotten out without chaos ensuing, I don't know how that happens," he told ABC News.
From 2009 to 2013, Mr Blinken served as deputy assistant to Mr Obama and as national security adviser to then-vice president Mr Biden.
During his tenure in the Obama administration, he helped to craft US policy on Afghanistan, Pakistan and Iran's nuclear programme.
Mr Blinken, seen as a quiet professional with less of the bombast of his predecessor, Mike Pompeo, will now be remembered for repeatedly reassuring Americans that the Afghan conflict would not end like the Vietnam War.
Even as Afghanistan's security forces were collapsing last week, he glumly repeated the assertion that the situation “is manifestly not Saigon”.
The reference relates to the chaos in the former South Vietnamese capital in 1975 as America lost that war.
But if anything, the images of desperate Afghans clinging to the side of a taxiing US C-17 cargo plane are even worse.
Jake Sullivan, Mr Biden’s National Security Adviser, admitted that the events in Afghanistan had unfolded with, “unexpected speed".
Mr Sullivan, 44, started his career of service as an assistant in the Obama administration.
One of his former colleagues, Brett Bruen, who was Mr Obama's director of global engagement, wrote an opinion piece in USA Today saying that Mr Sullivan should be the sacrificial lamb as the Biden administration unpicks the events of recent weeks.
“Biden wanted out of Afghanistan. It was on Sullivan to figure out how to achieve the president’s goal while ensuring we avoided potential pitfalls and problems. That’s clearly not what happened," Mr Bruen wrote.
Lloyd Austin was the commanding general of US forces in Iraq as they wound down their presence there in 2011.
He was opposed to a total US withdrawal and had argued for thousands of troops to remain to train and assist the Iraqi security forces.
A decade later, he is the Secretary of Defence as the Afghanistan crisis unfolds.
He has had to send thousands of extra troops into Afghanistan in recent days just to make sure the remaining US forces can leave safely, and to help extract thousands of US citizens and Afghans desperate to flee.
The Pentagon has even had to ask the Taliban to protect civilians heading to the airport.
Mr Khalilzad, the US special envoy on Afghanistan under former president Donald Trump, was kept in the job by the Biden administration and will face scrutiny for his role in the final years of the war.
Critics including Mr Biden have said the 2020 deal he negotiated with the Taliban surrendered too much US leverage and paved the way for the situation today.
Not only did the accord completely cut out the government led by Mr Ghani at the time, it awarded the Taliban broad concessions, including the withdrawal of all US troops, in return for only vague commitments and actions.
For instance, it mandated Mr Ghani’s government to release 5,000 Taliban prisoners before peace talks even got under way. In return, the Taliban had to release only 1,000 pro-Ghani captives.