Late on Sept. 11, 2001, Najib was at home with his family in Kabul listening to a radio bulletin on the Pashto language service of the BBC. There was no such thing as the internet in Afghanistan then, and with almost no other information sources apart from the Taliban's Voice of Sharia radio, the BBC's evening program became known as the "sixth prayer" of the day.

The newsreader said planes had been flown into buildings in New York City and Washington. Just 13 at the time, Najib turned to his uncle for answers. "We hadn't heard of America then, and I asked him: 'Where are New York and Washington?' My uncle said he did not know, but he thought maybe New York was a country."

Najib lived with his family in a cramped, mud-brick dwelling not far from the upscale Kabul neighborhood of Wazir Akbar Khan. Its high-walled houses and gardens were home at the time to many senior Taliban figures and their Arab al-Qaida allies. Najib would see them on his regular visits to the neighborhood, where he would wash car windshields or try to sell simple felt handicrafts made by his mother and sisters to supplement the family's meager income. Taliban rule meant they were mostly confined to their home.

The al-Qaida Arabs were not good customers, Najib remembers. More approachable were the handful of aid workers, diplomats and journalists also living in the area. They would often give him a few dollars, which both helped feed his family and allow him to go to school. He had also started picking up some English through his interactions with foreigners.

The effect of what Najib had heard on the radio was obvious the next day in Wazir Akbar Khan. As he walked about looking for business, he saw Taliban leaders, al-Qaida Arabs and their families and guards making hurried departures in SUVs. The panic spread in Kabul in the following days, with many people leaving for family villages outside. On nearby hilltops, Taliban fighters could be seen preparing anti-aircraft positions. America had not yet declared its war on terror, but everyone could guess what was coming. And by then Najib knew this was a country bigger than New York.

When we talked recently, he had another memory from that evening listening to the first reports of what the world came to know as 9/11. Najib recalled the newsreader mentioning a place called the White House being a possible target that day. "And I said to myself, 'What is this White House?' And, 'Why does it matter if this house is white?'"

Nearly 20 years later, Najib speaks excellent English. He has his own young family, and he has built a successful career. With his days as a street-seller in the past, he has realized a dream not only Americans would recognize and applaud. Except that he does not want me to use his real name or say what he does in case it identifies him. With the Taliban now in Kabul, he has fled with his immediate family, fearing he will be targeted for his work. And he still has some relatives left behind. "I felt so sad to leave," Najib told me. "But I had no choice."

The revolving door

This past spring, Najib watched a television broadcast from the White House that had so mystified him two decades ago -- and what he heard would change his life again. U.S. President Joe Biden announced an unconditional American withdrawal from Afghanistan, saying that "it's time to end the forever war."

Forever wars have been a theme of Afghanistan's history -- that and lessons unheeded. For three centuries, faraway empires have come to conquer -- the British in the 19th, the Soviets in the 20th and now the Americans in the 21st -- before retreating in humiliation. The U.S. boots on the ground since 2001 have effectively been a new iteration of America's entanglement in Afghanistan, after its covert intervention in the 1980s backing the anti-Soviet mujahedeen. The loose ends of that war helped pave the way for 9/11. Many of the same Afghan personalities have kept returning too, warlord figures who constantly change sides to stay in the game. And now it has been the turn of the Taliban to come triumphantly back.

Afghanistan, then, has become the ultimate symbol of a war that changes nothing -- except to spill more blood. At the end of the Cold War, there was hope for a while that the big ideological conflicts were over, ushering in a new era of cooperation and progress. Instead it yielded to two decades of brush fire wars between big states and nonstates. And now, once again, the world is perched on the edge of superpower conflict. Rather than a ladder to the end of history, there is a revolving door, for which Afghanistan is, once again, the gateway.

"We're engaged in a serious competition with China. We're dealing with the challenges on multiple fronts with Russia" Biden said last week, explaining his rationale for ending the U.S. presence in Afghanistan. "We have to shore up America's competitiveness to meet these new challenges in the competition for the 21st century."

Unspoken was the grim reality that after so much death and so much spent on high-tech conflict, the United States has so little to show for its post-9/11 wars. A dictator toppled in Iraq, but control handed -- at least in part -- to America's old rival, Iran. Back home, a country divided and where 31,000 active duty personnel or veterans who served in the Afghan and Iraq wars have committed suicide, more than four times the number who died on the battlefield. And now, just before the 20th anniversary of the al-Qaida attacks on New York and Washington, their hosts, the Taliban, are back in power.

Biden himself drew attention to the date, when he announced the end of America's war, saying then that all U.S. troops would be home before September 11. And he chose the exact same place in the White House where President George W. Bush had ordered its start in October 2001.

Looking back, Biden's announcement that he was pulling out was the signal the Taliban and their Pakistani backers had been patiently waiting for, ready to advance on towns and cities. But the fall of Kabul and the deadly chaos at the airport that followed were not preordained.

There were moments in the early months after Biden had ordered the troop pullout when he could have changed course. Evacuations could have started earlier. The White House narrative now is that no one realized the Afghan security forces would collapse so easily. Plenty of Afghan soldiers did fight though, and died, until their ammunition and food ran out, and the air power the Americans had taught them to rely on stopped coming.

Such debates seem almost moot now. It is clear that whatever happened on the ground, President Biden had already made up his mind to bring America's War on Terror to a screeching halt -- at least in Afghanistan. And in the process, he exposed all the contradictions on which it had been built.

Disconnect and denial

Covering the War on Terror as a journalist meant regular reporting trips to the archipelago of sprawling bases that the U.S. military and its allies constructed across Afghanistan and Iraq. Places like Bagram, Bastion, Salerno and KAF (or Kandahar Airfield), or Balad, Falcon and Speicher in Iraq have become mental landmarks of the conflicts, etched in soldiers' memories. Beyond these large bases was a constellation of smaller outposts.

The bigger military settlements had timed bus services to get troops and the armies of contractors supporting them from place to place. Kandahar in southern Afghanistan had pizza joints and coffee bars, even a TGI Friday at one point, multiple barbershops staffed by women from Kazakhstan and Kyrgyzstan and a giant military store where soldiers could choose from an astonishing range of televisions, DVD players and other electronics. It had a small book section too. Looking through on one visit, I saw a selection of beginners' guides to Arabic. No sign, though, of any books for Pashto or Dari, Afghanistan's two main languages.

Perhaps it was because the Afghan war was run by CENTCOM -- one of America's so-called regional combatant commands overseeing its forces around the globe -- whose main focus is the Middle East. But even now, after 20 years of war there, many Americans still refer to Afghanistan as being part of that region.

Somehow, it was the food choices that jarred most of all.

Kandahar is a starkly beautiful place. Sharp, angular ridges jut out of the harsh desert landscape that surrounds the air base and the nearby city. Oceans and green fields feel so far away as to be unimaginable. And yet on weekends, the troops stationed at Kandahar could look forward to "surf and turf" -- thanks to the cargo planes that shipped in vast quantities of refrigerated lobster and steak. No wonder that it reportedly cost more than $1 million a year to support just one soldier in Afghanistan at that time.

The same largesse was on display in Iraq, where some soldiers started to face a problem around the waistline that became known as "the Baghdad bulge." Commanders responded, by encouraging healthier eating. Even then, the message was confused. I remember visiting a dining facility, or DFAC, at a big U.S. base in southern Baghdad that had set up a "diet corner" with a good-looking selection of fresh salads. But it was dwarfed by the adjacent stand offering a full menu of Baskin-Robbins ice cream.

Soldiers need to eat of course. But for years, troops at these megabases could tuck into four hot meals a day if they wanted to. Their adversaries, whether insurgents in Afghanistan or Iraq, lived on a diet almost by definition. And meanwhile, in homes beyond the heavily guarded perimeter of Kandahar Airfield, there were always children who did not have enough to eat.

With its vast resources, the U.S. military could bring a pizza chain to an Afghan air base and transform it into a slice of America. It helped make U.S. contracting companies rich. But what was it all for? How did fresh lobster help fight terrorists? Surf and turf in the desert instead became a metaphor for disconnect and denial.

The blind eye

One morning when I was based in Kabul for the BBC I received a call from a colleague saying our reporter covering eastern Afghanistan had been taken away by U.S. soldiers after a night raid on his home. Kamal Sadat was a great source on events in this critical part of the country bordering Pakistan, where the Taliban had a bedrock of support. We worked together on reporting trips I made to his home city of Khost and nearby provinces.

But now his family had no idea where he was, and they had called asking for help. Kamal was a local celebrity at the time, thanks to his work for the BBC. With fewer competitors then, it was still one of the most important sources of information in the provinces, and when Kamal came on the radio from Khost, people listened. In the course of his reporting, he had often dealt with the American forces stationed at the large U.S. base on the edge of Khost, known as FOB (Forward Operating Base) Salerno. None of that prior knowledge apparently mattered.

A team of U.S. soldiers with an Afghan translator had broken down the family's door as they slept and then burst in, calling for Kamal to identify himself as they aimed their weapons at him and his terrified parents and siblings. "At first, I thought it was the Taliban," he said. When he realized the intruders were Americans, Kamal says he tried to reason with them, showing his ID cards in the hope of persuading them they had made a mistake.

But minutes later, handcuffed and blindfolded, he was being driven away in the darkness in a convoy of U.S. Humvees. In the midst of his nighttime abduction, there was also some dark comedy. The soldiers got lost finding their way back to their base, Kamal remembers. "After they took my blindfold off I could see where we were, and I directed them."

That, we found out later.

After the alert from his family, we started calling U.S. military contacts, demanding to know what had happened to a recognized and well-known journalist. At first, we got nothing back. For all intents and purposes, Kamal had disappeared.

Early the next day, I got a message saying Kamal was no longer in Khost, but in a cell in the prison at America's main air base at Bagram. This was the same Bagram prison that had become notorious for inmates being tortured -- in what became Afghanistan's version of Abu Ghraib. Two Afghan detainees died there at the hands of U.S. soldiers in 2002, their fates pieced together by The New York Times' Carlotta Gall.

We were told Kamal had been labeled a "threat," as a result of some unspecified information the U.S. military had obtained. Some of these tipoffs did concern individuals directly linked to attacks on U.S.-led forces and their Afghan allies. But Kamal is convinced a rival in his hometown spoke against him to the Americans to trigger their nighttime raid.

It was an all too common story. People being lifted out of their homes -- or bombed from the air -- as a result of false leads, or tips fed in by someone using the Americans to settle a score. Open-air wedding parties were hit so often by U.S. airstrikes that such incidents became one of the signature horrors of the conflict, alongside the mass casualty suicide bombings of the Taliban and Islamic State group.

Two days later, the Americans released Kamal, apologizing to him and his family, explaining that his detention had been based on "a misunderstanding." He welcomed their apology, saying, "I understand it was a mistake by the U.S. Army."

The point to this story is really about all the other Afghans who did not have Kamal's profile and contacts, and the impact these aggressive U.S. tactics had on public attitudes to their presence, especially in rural areas where most such actions occurred.

Former Afghan President Hamid Karzai, much criticized for the way he turned a blind eye to corruption within his own ranks, was prescient in warning the Americans early on of the damage they were doing to their cause by continuing with their heavy-handed raids and airstrikes.

"We fight them there so we don't have to fight them here," was one of the mantras of the war on terror, for both America and its allies, from Afghanistan to Iraq, with the implication for voters back home that the big risks could be outsourced and forgotten. But it became a self-fulfilling phrase. The more they fought "there," the more the "them" turned against the Americans.

Almost to the end of the U.S. presence in Afghanistan, its special forces were employing such tactics, partnering with Afghan commandos they had trained. Many of those killed and captured in these raids or strikes were linked to the Taliban or, later on, the Islamic State group. Yet even American officers sometimes compared the war to the whack-a-mole arcade game, acknowledging that the Taliban were constantly able to absorb their losses and return with new recruits from havens in Pakistan. Today, former U.S. commanders admit those sanctuaries and consistent Pakistani support rendered the war unwinnable.

"[The Americans] never accepted that Pakistan had strategic autonomy, and would pursue its interests as it saw them," said Husain Haqqani, a former Pakistani ambassador to Washington. Now an academic in exile in the U.S., he fell out with his government after American forces found and killed Osama bin Laden in Pakistan in 2011. But U.S. policymakers too often see things through their own prism, Haqqani argues, assuming everyone must want what America wants. "There is an innate U.S. assumption that they can change the calculus of other countries simply through incentives and coercion, and get them to do what America wants."

Neither generals nor politicians showed much interest in changing the strategy, or the thinking behind it. And the only interest most Americans have had in Afghanistan in recent years is in getting out -- something opinion polls still make clear. So there was little political pushback when the Trump Administration agreed a notably generous withdrawal deal with the Taliban in February last year.

Signed in the Qatari capital, Doha, where the Taliban have had their unofficial embassy, the deal committed the U.S. to pull all its forces out by May 1 this year. In return, the Taliban agreed to rein in al-Qaida on Afghan territory, and not to attack departing U.S. troops. It also got a so-called "confidence-building" incentive of 5,000 Taliban prisoners being released.

Protests from the Afghan government that this would just bolster Taliban ranks were dismissed. It wasn't even part of the deal, because it was excluded from the talks. But the only thing President Biden changed when he took over was the final departure date. Safe in their homes in Pakistan and Qatar, Taliban leaders kept up the pretence of talking while their fighters prepared, biding their time and waiting to capitalize on past US mistakes.

The self-inflicted defeat

There were really several wars on terror in Afghanistan at once. The one fought with night raids and air strikes was mostly concentrated in rural villages and small towns where the Taliban had their best footholds -- and also where most Afghans live. There were valiant efforts by Afghan and foreign journalists to report what was happening on these more remote front lines. But much of the time the rural war on terror was off camera and out of mind. That made it easier for the Americans to see themselves as the good guys, and dismiss notions that they were occupiers from a foreign land.

It was a more nuanced war that played out in the capital Kabul, where the media focus lay. And in the last few years, it was a largely one-sided conflict, with the Taliban and Islamic State group using suicide bombs and assassinations to spread terror and undermine the government. But there was still development and change. Kabul's youth majority had created a whole new culture, connected to the world. The defiant online response to the Taliban's takeover is one sign of that, with young women taking the lead in many of the street protests in Kabul.

It is commonly asked today, in the wake of their victory, if the Taliban have changed. There is no question that Afghanistan has. And this goes to the heart of the question over Biden's decision to call this a "forever war" and then pull out.

Flawed though they may have been, the Afghan security forces were holding the line in the cities, with the backstop of the American presence. It was that combination that allowed another presidential election to take place two years ago, Afghanistan's fourth since the Taliban were last in power in 2001.

But there-in also lay another fundamental weakness of the American project. That 2019 vote --- giving former President Ashraf Ghani a second term -- was marred by rampant fraud. With each election, the extent of the abuses became more widespread and blatant -- with the turnout falling in parallel. Yet there was no doubting the initial enthusiasm Afghan women and men showed for electing their leaders at the first presidential election in 2004, when the lines of waiting voters stretched for blocks. It's patronizing to claim -- as some do now -- that Afghans can't do democracy. The problem was the kind of democracy they were given.

The disputes that erupted over vote-rigging sometimes left Afghanistan without a government for months on end. But each time, American envoys would come in to fix a deal, paper things over and move on.

Crucially, this democratic disconnect was most glaring in the rural areas, where the few government services were more likely to be servicing themselves by taking bribes. This was where the ballot-stuffing and vote-rigging was usually worst, overseen by old power brokers carving things up under prearranged deals.

The way rural districts fell to the Taliban this spring and summer was telling. But with a different attitude in Washington to U.S. involvement in Afghanistan -- not getting so hung up on phrases like "forever war" and the mistakes of the past -- there is little doubt that a different outcome was possible.

No American politician in power now is calling to end the "forever war" in South Korea, where far greater numbers of U.S. troops have been based for decades. The situations may be different -- but not so much. Until the terrible carnage after the suicide bomb at Kabul airport, no American service personnel had died in Afghanistan in nearly two years. Ultimately, it is about political choices, and in his angry response to his critics, Biden was saying Afghanistan no longer mattered. So whether it was a war on terror, or a campaign to bring democracy and women's rights, this was at least partly a self-inflicted defeat.

The timing made it worse, with Taliban fighters rolling into Kabul in seized American vehicles and packing the latest US weapons just before the 20th anniversary of the 9/11 attacks. It has been a humiliating blow to America's credibility and self-image.

Will the United States learn any lessons? Husain Haqqani is not sure. "There is this hubris to America," he says. "It is a country with so much power. It wins big, it loses big. A few books get written, a few movies, then it moves on."

Twenty years ago, the superpower needed revenge for the nearly 3,000 people who died on that terrible September day and the blow to its sense of itself. And the people demanded it.

"U-S-A, U-S-A, U-S-A," came the defiant but anxious chant from a crowd of people wrapped in the Stars and Stripes at an impromptu rally near Boston in the days afterward. Two of the hijacked planes took off from its airport, and so I had been sent there to report on the reaction. What I also remember was doing stories on American Muslims and Sikhs who were hiding in their homes, after others of their faith had been attacked.

Nearly 10 years later, I was outside the White House on the night then-President Barack Obama announced that Osama bin Laden had been found in Pakistan and killed, reporting on the crowds that came to celebrate. And I heard the same chant again. "U-S-A, U-S-A, U-S-A."

By a conservative estimate, at least 400,000 civilians have died in the wars that followed 9/11 in Afghanistan and Iraq. Many due to insurgent bombs and bullets, but tens of thousands of them because of weapons fired by Americans who had come to their countries from far away.

"It was us, the Afghans, who paid the price for your war on terror," said Najib, now trying to set up a new life in a new country.

Andrew North is a former BBC correspondent in Afghanistan and Iraq and continues to cover both countries as an independent journalist and commentator