I'm a photographer who covered 9/11 and its aftermath. Here are the most gripping photos I took, and the stories behind them

• From the first moments after the attacks of Sept. 11, 2001, journalists were on the scene documenting the horror and tragedy of that day.
• U.S. troops entered Afghanistan less than a month later and, soon after, prisoners began arriving at the Guantánamo Bay prison.
• 20 years later, photographer Alan Chin recalls covering those events and the images he captured.

Twenty years is a long time, long enough to forget what the texture of daily life was like. I think back to that September day in New York, and the six months that came after - when I traveled to Afghanistan, to witness the early months of the war, and then to Cuba, to see the Guantánamo Bay prison. I had a cellphone, but not a digital camera. My internet was dial-up and I was driving a 1987 Mazda. My parents were alive and well.

Those were years when I traveled a lot as a photojournalist: China, the Balkans, Afghanistan and Central Asia, Israel and Palestine. But I was home in New York on Sept. 11, 2001.

It was the ringing telephone that woke me up. My late brother, Bonlap, was calling from Michigan to say that planes were striking the Twin Towers. From my apartment on Manhattan's Lower East Side, I could already hear sirens from emergency vehicles barreling downtown. I turned on the TV, but couldn't get any reception except for one faint, fuzzy station with a live feed. (The broadcast antenna itself was on top of the World Trade Center and no longer working.) The full import of what was occurring had not yet set in. "I think this will be a long day, don't expect to hear from me until late," I said to my then-partner as I headed out the door, as if this were simply a serious, but not necessarily desperate, crisis.

I hopped onto my bike and rushed as fast as I could toward the burning towers. I left my bike at City Hall and started walking down Vesey Street until I reached the corner of Church Street - directly across from the World Trade Center. Out of the corner of my eye, I saw what I thought was debris falling from the North Tower. But behind me, I heard a horrified voice say, "Oh my God. Another one." I realized that the debris was a person, a person who had just plummeted hundreds of feet to certain death.

I had time to shoot one roll of film. I was looking down to reload one of my cameras when people around me on the sidewalk started screaming. The South Tower was exploding with an enormous cloud of flame and grey smoke bursting out. I ran with a few police officers and firefighters into the basement of an office building, thinking that the tower might fall on top of us. For long minutes, we struggled to find another exit from that building, hopefully onto the next street, anywhere that was further away.

When we emerged, the entire world had changed. The bright blue sky had been replaced by twilight gloom. The air was filled with thick smoke. Scraps of paper drifted in the wind, and the headstones of the cemetery next to St. Paul's Church were covered with ash. My late father, who knew I'd rushed to the towers, watched the explosion from a Chinatown coffee shop where he had gone for breakfast. He told me later that he was sure I was dead.

I retreated a block to Park Row, where stunned people covered in dust were boarding a city bus to escape the area. Then, I turned back. At Broadway and Fulton, I felt a low rumble - the North Tower starting to come down - and I ran down the stairs of a subway entrance so quickly that I fell and cut open the palm of my hand, covering myself in blood. I tore a piece of fabric from my shirt to make a bandage. I found myself totally alone in that subway landing, with smoke and dust churning in the dim light. Time and space seemed all confused and the universe turned upside down. It was 10:28 AM - 29 minutes had elapsed since the South Tower collapsed. But in my mind I could not have determined if it were five minutes or five hours.

Over the next few hours, I photographed shattered firefighters, some desperately calling on their radios to colleagues that weren't responding. Later, I followed them onto the remnants of the South Tower from the Hudson River side, as they vainly searched for survivors.

I worked entirely on autopilot and made a complete circuit of what became known as Ground Zero.

At one point, I ran into an old friend, journalist David Rohde, and we walked together for a time. We were standing close to the inferno, but we couldn't see very much. But then, for one moment, the wind shifted, and we saw, for the first time, all that was left: that jagged section of twisted metal. David turned to me and said, "That…was…the World Trade Center."

Allies and enemies, enemies and allies

Less than a month later - on Oct. 7, 2001 - the U.S. military launched the first bombing campaign targeting the Taliban in Afghanistan. A month after that, I got an assignment to go to northern Afghanistan. I had covered the Taliban's early days in power four years earlier, in 1996, and this would be my third trip to the country.

Taking off from JFK airport, the plane made a wide banking turn over Manhattan to head out across the Atlantic and I could see the smoke still rising from the enormous pit that was known then as Ground Zero.

From Termez in Uzbekistan, I crossed the Amu Darya River on board an Uzbek military boat and crossed into northern Afghanistan.

Former enemies from the decade-long Soviet occupation (during which the U.S. had backed the anti-Soviet mujahideen) and both allies and enemies from the civil war that followed, had once again formed alliances. Abdul Rashid Dostum, a pro-Soviet general, and Atta Mohammed Noor, a mujahedeen commander, were back in charge. They had defeated the Taliban across much of northern Afghanistan with the help of American air support, Special Forces teams, and French paratroopers securing the airport in Mazar-i-Sharif. (Fast forward to today and Dostum and Noor's son, both of whom fled Afghanistan after the Taliban again took control of Afghanistan, are now negotiating a deal.)

I had first encountered Dostum at the fateful meeting in 1996 when he, Ahmed Shah Massoud, and Karim Khalili had formed the Northern Alliance, or United Front, against the Taliban. Their soldiers had repelled a Taliban offensive in 1997, and massacred thousands of the Taliban prisoners they had captured. In turn, thousands of civilians and combatants were massacred by the Taliban when they reoccupied Mazar-i-Sharif in 1998. A group of Iranian diplomats were killed by the Taliban at that time as well. In those five years, from 1996 to 2001, Dostum and other warlords had repeatedly fled the country and returned, fought each other as well as against the Taliban.

Now, they were allied with the U.S. and coalition forces. I had come to Mazar-i-Sharif, Afghanistan's fourth largest city, to document that.

When I arrived in November, the fighting in the area seemed to be mostly over. Despite its recent brutal history, the city was outwardly little different from the last time I had visited. The iconic Blue Mosque, Shrine of Hazrat Ali Mazar and an Islamic holy site, still hosted flocks of white doves as it had for centuries. Most women wore burqas - but not all. Air Force flights from as far away as Germany were dropping American military and humanitarian food packets in an effort to win hearts and minds. U.S. Army jackets, sleeping bags, and other assistance items were on sale at the markets, having reached the black market barely a month into the war.

Up to 5000 Taliban fighters including many foreign militants had surrendered in Kunduz, and up to 500 of them had just been killed in a violent uprising at the Qala-i-Jangi fortress.

Attending a meeting that Dostum held to dispense favors to elders and local leaders who had come to sing his praises and plead for assistance, I asked Dostum what had happened to his Cadillac, which I'd heard on my last visit was the only one in Afghanistan. "Oh, the Taliban took it!" he said with a laugh.

I also learned that the surviving Taliban captives were being held in a prison 50 miles to the west, in Sheberghan, close to Dostum's home palace. Dostum gave journalists permission to visit.

On my first trip to the prison, I saw container trucks bringing in new prisoners. Overcrowded, and without food, water, or ventilation for several days, the prisoners told us that at least hundreds had already died in those containers. There were also reports of summary executions and of soldiers opening fire on some of the containers packed with prisoners inside. I spoke with the International Committee of the Red Cross (ICRC) staffers who facilitated the prisoners' first contact with their families, as prescribed by the Geneva Conventions. (The U.S. military said they would follow these conventions even as they refused to accord the legal status of prisoners-of-war to their "detainees.") The ICRC said that the prison was overcrowded and unsanitary, with an outbreak of dysentery.

A few days later, regular U.S. Army soldiers from the 10th Mountain Division arrived and photographed, fingerprinted, and took DNA swabs from each prisoner. They allowed me to photograph this process - but not the 85 or more prisoners they removed. I later wondered if some of them had ended up at Guantánamo Bay, which would begin receiving "enemy combatants" outside the reach of U.S. and international law on Jan. 11, 2002.

Physicians for Human Rights later investigated and found mass graves at Dasht-i-Leili nearby, confirming that a massacre had occurred. But this one happened with American Special Forces and other US military teams either present or very close by, embedded as they were with their Afghan allies. It was a war crime of major proportions, but despite ample reporting and President Obama's promise in 2009 to investigate, no report has yet been published.

Over the next few weeks, I traveled around northern Afghanistan and witnessed a confused series of skirmishes and battles between different Northern Alliance and/or Taliban units. They all seemed as quick to settle old scores with each other as much as anything else. In one instance I saw evidence of hastily evacuated American forces who left equipment behind at a camp overrun by one Northern Alliance group against another. In another incident, civilians were wounded in an American air strike. The Taliban, then as now, had often succeeded not with military prowess but with groups defecting from their previous allegiances to join them, and their 2001-02 collapse was much the same as many of their erstwhile supporters abandoned them. It was hard for a foreign journalist to understand the complexities of these loyalties.

What has stuck in my mind all these years later is a conversation I had - I'm recalling it from memory now - with one of the young and largely self-taught Afghan interpreters who had sought employment from aid workers and journalists.

The foreign press corps was staying at the only hotel in Mazar-i-sharif, a seven-story building in the center of town. One day, we were on the hotel's rooftop, which we were using to position our satellite phones and modems.

"This is one of the highest buildings in Mazar. I've never been up here before," the interpreter, whose name I don't remember, said to me and several of my colleagues. "The people on the street, they look so small."

There was indeed a lovely view of the Blue Mosque below us. He asked, "So, the reason all of you coming here and America being at war in Afghanistan is because of those tall buildings that were destroyed in New York, is that correct?"

"Yes, that's right," we answered.

"And, those buildings," he continued, "those buildings that were destroyed…were they as tall as this one?"

Two days at Gitmo

Several months later, in March 2002, I was invited along with a small group of journalists to visit Guantánamo Bay where, the Bush administration insisted, the most dangerous al-Qaeda and Taliban prisoners were being held. Following instructions, I hurried to the Roosevelt Roads Naval Station in Puerto Rico and arrived in the middle of the night. I slept on a bench at the base gates until the dawn departure to Cuba on board a passenger plane chartered by the military that was still painted in its former Pan Am Airlines livery.

The Navy put us up in a motel-style building and public affairs officers were assigned to be our minders. We were told we would have a packed schedule over the two days we were there.

We were shown a display of what each arriving prisoner would be given, including the soon-to-be-infamous orange jumpsuits. They pointed out the McDonald's and jerk chicken restaurants - attempts by the military, as I'd observed at American military installations worldwide, to make soldiers feel more at home. We spoke to Jamaican civilian workers who were paid $4 an hour, less than the $5.15 federal minimum wage. The Muslim chaplain, Marine Lt. Abuhena Mohammad Saiful-Islam, spoke about ministering to the prisoners' spiritual needs, and commandant Marine Brig. General Michael Lehnert said that he was committed to humane treatment.

But what we journalists got was the illusion, rather than the reality, of access. We all realized that by accepting the invitation to visit Guantánamo Bay, we had facilitated the government's claims of transparency, when in fact the very opposite was the case. On the pristine Caribbean beach by our motel - a beach that was unsullied by buildings or other people - we reflected on this irony, and lobbied for more access - entirely unsuccessfully.

And so, we barely got to see Camp X-Ray, the detention camp that had originally been built to house Cuban asylum seekers and was now repurposed for the Global War on Terror. We were kept 300 feet away, where only the distant sight of people behind razor wire wearing those orange jumpsuits even indicated that there were any prisoners at all. We weren't allowed to see any actual living quarters or common areas, let alone speak to inmates, or see them up close.

In later years, harrowing details emerged of force-feeding, torture, and hunger strikes, as those held at Guantanamo continued to be denied access to their families, attorneys, and access to journalists. At its peak, 675 prisoners were held there. On President Obama's third day in office, in 2009, he signed an order that Guantanamo Bay would be closed "as soon as practicable, and no later than one year from the date of this order." There was a plan to put Khalid Sheikh Mohammed, the accused 9/11 mastermind, on trial in lower Manhattan, at a courthouse that's just a short walk east of Ground Zero. None of it came to pass. Today, 20 years after the Sept. 11 attacks, 39 prisoners remain at Guantanamo Bay - all, for far, without a trial.

"Even in the earliest days of Guantánamo, I became more and more convinced that many of the detainees should never have been sent in the first place," Retired General Michael Lehnert, who had supervised the construction of the detention camp and served as its first commandant, wrote in the Detroit Free Press in 2013. "They had little intelligence value, and there was insufficient evidence linking them to war crimes. That remains the case today for many, if not most, of the detainees…It is time to close Guantánamo."

Twenty years is a long time. In 2021, the median age in Afghanistan is 18. Among the 180 people killed in a suicide attack on Aug. 26 at Kabul's airport was 20-year-old Lance Cpl. Rylee McCollum, who was a baby on the day of the Sept. 11 attacks. Even as the American war in Afghanistan ends in both ignominy and relief, the ongoing conflicts there and in dozens of other places continue. My own photographs sometimes feel unfamiliar. The film and contact sheets bear grease pencil marks from old edits; the notes both handwritten and typed sometimes refer to people and places I must look up to remind myself of forgotten details. And then, suddenly, it is shockingly immediate once again.