Genelle Guzman woke on the morning of Sept. 12, 2001, in a terrible darkness, unable to move, feeling her 30-year-old body fading. Her head was wedged between broken slabs of concrete, and her legs were pinned beneath something she could not see. She had spent the long night flitting in and out of consciousness, but she was alert now, jarred awake by pain, and aware of the essential facts of the previous day: Her workplace, the World Trade Center’s North Tower, had collapsed, and she was buried alive.

She found that she could move her left arm, which she used to clear away the dust that coated her eyes and face. But in the blackness she could not see her wristwatch, and had no way of judging how long she had been trapped. With her fingers she probed the edges of her tomb, which at first had felt unbearably hot but had now turned cold. She tugged at something soft directly beneath her. It was fabric, of some kind. A piece of clothing. She let it go.

Outside, a full day had passed. Americans were absorbing the shock of the terrorist attacks on New York and Washington, when history turned in a single hour. In the vast debris field where the World Trade Center had stood, firefighters had long ago rescued the last of the handful of people who were found alive, huddled in a stairwell or in underground passageways. Now K-9 recovery teams were beginning their grim work, sniffing through rubble piles less than 100 feet from where Guzman lay.

Guzman could hear nothing of the world above her. In her wakefulness, the Trinidadian immigrant and clerical worker took inventory of her injuries, willing her mind to survey every inch of skin and muscle along her shattered legs. She repeated remembered prayers and offered up new ones. She made promises to God, and to herself.

Her thoughts returned again to the previous morning, Sept. 11. She had just arrived for her temp job on the North Tower’s 64th floor, and was chatting with another worker over a bagel when it happened. First came a strange booming sound, like a distant explosion, and then the terrifying sensation of swaying, as the top floors of the 110-story building swung outward and back again, like a palm tree bending with the wind. She ran to a window and gaped at the strange spectacle of thousands of pieces of paper floating in midair, like a confetti squall more than 60 stories above the ground.

She should have fled at once, as others did. But she had not heard an order to evacuate, and Guzman, who had overstayed her U.S. visa and didn’t want to draw attention to herself, was afraid to leave her post without permission. So she sat with her friend, a fellow secretary named Rosa, and the two made phone calls and waited together for more than an hour. Finally, when smoke began visibly wafting from the elevator shafts, the women joined a group of stragglers that was headed toward one of the emergency stairwells. Holding hands, the two friends began the slow descent in their dress heels, starting at the 64th floor and continuing downward, through the 50s and then the 40s, passing firefighters who called out words of encouragement as they trudged upstairs against the tide of office workers.

Her group had made it to the 13th floor when Guzman decided that her heels finally had to go. She paused and stooped, just long enough to slip off a shoe. And as she did, the walls of the stairwell exploded around her. She felt Rosa’s hand slip away, and then the stairs disappeared, along with walls and railings and people. She crouched and shielded her face as hundreds of unseen objects collided and smashed all around her. Everything went dark, and Guzman believed she would die. By an unfathomable chance, she did not.

After lying for hours inside the tiny cavity that both protected and entombed her, she became dimly aware of sounds: A siren. The beeping of a truck that was backing up somewhere, not far away. And then a voice. Someone was yelling something.

Guzman summoned up all her energy and shouted back, as loudly as she could.

As she had done many times, Guzman used her free hand to claw at the loose rubble in the gaps between the concrete slabs above her. This time, some of debris gave away, and she could see a faint gray light. She dug some more, and soon found that the hole was big enough that she could squeeze her hand through it.

From the other side, another hand grasped hers.

“I’ve got you,” her rescuer said.

It took more than an hour to remove the steel beams that had pinned Guzman’s legs. Afterward, she felt herself being lifted into the sunlight and gently placed in a basket-like stretcher. The rescue workers formed a human chain, and the basket was passed along the line of helmeted figures, down the treacherous slopes of the debris pile to the street below. At the bottom, a sudden roar erupted from the throng of firefighters and police officers. It was a spontaneous outburst of cheers for the rescue of Guzman, who, after 27 hours trapped in the rubble, was the last person pulled alive from the ruins of the World Trade Center.

In complete bewilderment, she looked up into the face of a medical technician.

“Are you taking me home?” she asked.

Like Fort Sumter or Pearl Harbor, the 9/11 attacks on New York and Washington were events that seemed to cleave history itself, carving America’s timeline into a “before” and “after” that existed in entirely different dimensions. On Sept. 12, the country awakened to find itself on a profoundly different course.

The attacks sparked two wars, both longer by far than any in U.S. history, which together claimed more than 6,500 American lives in addition to the hundreds of thousands of Afghans and Iraqis killed. The toll also included more than 50,000 Americans wounded, many of whom will require decades of care, and, for hundreds of thousands of military families, the strain of endless overseas deployments in pursuit of objectives that grew ever more opaque, right up to the Afghan war’s chaotic conclusion in 2021. Americans confronted a dangerous new foe — al-Qaeda — that was beaten back again and again, only to mutate into deadlier variants. A global “war” against terrorism spawned new bureaucracies and new industries. It changed the way Americans traveled, and altered Americans’ perceptions about their security and privacy. It challenged long-held legal and ethical norms for the handling of captives and prisoners. It gave rise to new rules, new weapons and new methods for capturing and killing the country’s enemies. Within the maelstrom, individual lives were transformed, their trajectories forever altered as the United States and the world were buffeted by the forces unleashed by the attacks.

On Sept. 12, Ronie Huddleston, a veteran of the first Iraq war, repacked his gear after receiving orders to prepare for a new combat mission. Soon he was overseas again, in the first of a series of tours that ended with a roadside bomb explosion and severe brain injury outside the Iraqi city of Kirkuk. The road home was long and painful. And he eventually watched with a mixture of fear and pride as his stepson enlisted in the Army and shipped out to the same Iraqi outpost where Huddleston had served 14 years earlier.

On Sept. 12, New York firefighter Raymond Pfeifer, covered in dust and soot, scoured the ruins of the World Trade Center in a desperate search for 11 men from his fire station who had been inside the South Tower when it collapsed. One name on the list carried a special emotional weight: It belonged to a 38-year-old father of two who had traded shifts with Pfeifer and was working in his place on 9/11. Pfeifer eventually spent months digging through the rubble, exposing himself to toxic chemicals.

Just uptown from Ground Zero, a young Wall Street lawyer named Hina Shamsi had been on her way to work on the morning of the attacks and witnessed the collapse of the South Tower from a crowded street corner in Lower Manhattan. A Pakistan native who had long admired American traditions of equal justice and the rule of law, she watched in dismay over the following months as U.S. officials appeared to toss aside centuries-old legal protections to allow torture, indefinite detention without trial and targeted killings, all in the name of national security. Shamsi eventually fought multiple courtroom battles in an attempt to force the country’s leaders to honor the values the United States had long professed.

Across the Atlantic, in Hamburg, Germany, Moroccan immigrant Mariam el Fazazi learned the names of the suspects in the attacks and discovered a horrifying connection: The lead hijacker had been a regular at her mosque, a place where her own father sometimes preached as a visiting imam, and a gathering spot for Hamburg’s radical Islamists. The discovery jarred her into beginning a years-long struggle to reclaim her faith from violent extremists within her family and neighborhood.

The most sweeping impacts of Sept. 11 have been obscured by time. They are, for most Americans, “normal,” as unremarkable as the ceremonies and tributes that occur every year in mid-September. But the cataclysm that was 9/11 was not contained to a single day, or to a handful of locations. Over the two decades that followed, destinies were upturned, reshaped and recast, for Pfeifer, Huddleston, Guzman, Shamsi, Fazazi and millions of others who had no inkling about what was to come.

Raymond Pfeifer did not come home on Sept. 12. Nor did he return to his Long Island family the following day, or the day after that. An entire 11-man shift from his fire station had gone missing at the World Trade Center, and Pfeifer, along with the rest of his unit from Manhattan’s Engine 40 Ladder 35, would spend months searching for them, and for the 332 other firefighters and thousands of other victims at Ground Zero. For the first six weeks, he labored without a break, taking catnaps in his truck and returning to the fire station to shower and sleep before heading out again.

His wife, Caryn Pfeifer, worried about him constantly. When conditions allowed, she made the trek from Long Island with fresh clothes, food and personal items. On her first trip, she arrived at a fire station that felt like a wake. Firefighters’ families had gathered in the station’s kitchen and living quarters, some to visit loved ones or bring supplies, as she had done. But others — the wives and children of the missing — simply waited quietly for news from the search.

Among the women, there was one in particular whom Caryn Pfeifer could not will herself to face. It was the wife of Steven Mercado, a handsome and well-liked firefighter from the Bronx. Because of their complementary work schedules, Ray Pfeifer and Mercado had become “mutuals,” meaning they regularly swapped shifts whenever one of them needed an extra day off for an outing or an appointment. Mercado had agreed to work on Sept. 11 so that Pfeifer could go on a golf trip with other firefighters. The two wives, also friends, were both painfully aware that Mercado had worked that day in Pfeifer’s place. Pfeifer was on the golf course at the moment the station’s dispatcher issued an all-hands alert that sent everyone racing to Lower Manhattan. Mercado was inside the South Tower when it collapsed. Pfeifer arrived at the scene more than an hour later.

Caryn Pfeifer kept her awkward vigil inside the firehouse until her husband finally arrived, exhausted and ghostlike, covered from helmet to boots in dust and ash from the day’s work. She had not seen him since before the attack.

“He was completely white,” she said, remembering the moment years later. “I looked at him and I almost died.

“I just remember asking, ‘Are you okay?’ He just shook his head. Dumb question.”

Winter had turned to spring by the time Engine 40’s men resumed normal routines and slept regularly in their own beds. Pfeifer came home, but after nine months at Ground Zero, he was a changed man. Once, he had been the gregarious, wisecracking social chairman of the firefighting community on Manhattan’s Upper West Side, the guy who knew everyone and was always the automatic choice when the station needed an organizer for Christmas parties and charity events. He was a doting father to his children, Terence and Taylor — ages 9 and 8 at the time of the Sept. 11 attacks — signing up to coach their soccer teams and showing up at every game and dance recital. Both kids earned coolness points when Pfeifer would allow them and their friends to ride in the firetruck through Times Square during a charity event.

That dad was lost in the rubble of the World Trade Center. Pfeifer became withdrawn, moody and short-tempered. Inwardly, he was grieving over his friends, and racked with guilt over the death of Mercado. But to his family, the emotions spilled out as anger.

“He always said the same thing: ‘I wish I had died on that day,’ ” Caryn Pfeifer said. “That was his main thing. It was like he was dead, from that day on, because of the guilt. Because he could still be with his kids every day, and the others could not. It was horrible, horrible, horrible guilt.”

The event that finally brought him back occurred years later when both children were in high school. The family noticed that Pfeifer had begun walking with a pronounced limp, perhaps from one of the many bumps and scrapes that came with the job. After some prodding, Pfeifer agreed to have his leg X-rayed. His son, Terence, who was 17 at the time, remembered coming home one day to find his parents quietly discussing the results. It was cancer.

“There was a huge mass in his leg and his bone was completely deteriorated,” Terence said. “They put him in the hospital and ran tests on him, and he stayed for a long time. That’s when they found out that it was his kidneys — renal cancer — and it had spread to his bones. And it was at Stage 4.”

It was a devastating blow, and yet Ray Pfeifer seemed to take it stride. After absorbing the news, he appeared to relax. It was as though, as his wife later said, the diagnosis had delivered a kind of relief. His doctors concluded that the cancer was probably caused by his months of exposure to toxins during the recovery mission in Lower Manhattan. In a way, his fate had been sealed on Sept. 11, just as it had been for his comrades who died in the collapse of the South Tower.

“It seemed to make him feel a little better,” Caryn Pfeifer said. “He was thinking that he should go through this. That it was his turn to be punished now.”

The cancer diagnosis appeared to give Pfeifer new energy. Leg surgery made it impossible for him to chase fires, but Pfeifer believed he had important work to do, including helping other Sept. 11 first responders like himself, and their families. It was clear to his family that he had been given two great gifts: forgiveness and a sense of purpose. The old Ray Pfeifer came roaring back, so much so that it was hard at times to believe he was really sick.

“The sarcasm was back. He was joking again. He just wanted to be around us all the time,” Terence Pfeifer said.

“He even put a sign on his bedroom door. It said, ‘I intend to live forever. So far, so good.’ ”

Few places outside the United States felt the reverberations from the attacks more than the port city of Hamburg. Often they arrived in the form of an unexpected knock on the door or a late-night phone call, as police fixed their attention on the increasingly anxious immigrant neighborhoods where three of the 9/11 hijackers and several al-Qaeda associates had recently lived.

One of those calls came to the apartment of Mariam el Fazazi, in the city’s St. Georg district. The 23-year-old Moroccan had moved to Hamburg only a few days before the 9/11 attacks, as the new bride of a French Algerian man who had charmed her with promises of a prosperous life in Europe. But her husband, Naamen Meziche, was nearly a decade older and sternly religious, and it was soon clear that his entire world revolved around a controversial mosque a short walk from their home where some worshipers advocated violence against perceived enemies of Islam. Among them was Mohamed Atta, the lead hijacker and the man who flew American Airlines Flight 11 into the World Trade Center’s North Tower, as well as two other pilots on the hijacked planes, Marwan al-Shehhi and Ziad Jarrah.

Being a stranger to Germany, Fazazi was, at the time, utterly dependent on her husband, and submissive to his views on where to go, and how to dress and behave. Fazazi wore a traditional Muslim head covering, the hijab, but her husband insisted that she also wear an abaya, a black robe that covered her body from head to foot. She was rarely allowed to leave the couple’s apartment except to shop for groceries or to attend services at al-Quds Mosque, where she sat in the partitioned women’s prayer room while her husband knelt with other men in the main hall. Walking home from the mosque afterward, the couple would pass bakeries, ice cream shops and cafes along the bustling thoroughfare called Lange Reihe. But Meziche would never consent to stopping at any of them.

“It is a sin to sit with the kafir,” or infidel, she recalled him saying. “Everything from German culture is haram.” Forbidden.

Fazazi in those early weeks did not ask her husband directly about his politics or his possible connections with the 9/11 hijackers. But she knew Meziche was acquainted with several members of Atta’s al-Qaeda cell and had met them at al-Quds Mosque, where he prayed up to five times a day. He was personal friends with several men who were part of a larger radical group with ties to al-Qaeda. It was hardly a surprise that the police came around asking questions. They first called the apartment a few days after the attacks, and asked Meziche if he would come voluntarily to the precinct station. He dutifully complied, and the investigators kept him for a few hours, showing him photographs and pressing him about the people he knew. Then, apparently satisfied, they allowed him to leave.

The police call and visit were quickly forgotten. Yet, for both husband and wife, the moment became strangely clarifying. Meziche, who had expressed surprise and shock in the immediate aftermath of the attacks in New York, began to align himself even more starkly with the Islamist militant ideals that the 9/11 hijackers professed, and that some of al-Quds Mosque’s preachers so loudly proclaimed. In his new way of thinking, he was part of the “resistance,” Fazazi explained.

“He had an idea in his head, and that was to go the way of jihad,” she said. “That was his aim in life, and he wasn’t going to let go of that.”

Fazazi was embracing a kind of resistance as well, but hers was of a very different sort. She began to question the interpretation of Islam that condoned the slaughter of innocent people. She began rebelling against an extremist mind-set that regarded women as inferior creatures to be controlled and cloistered.

“I always wanted to live a free and independent life,” she said. “I felt I was very different from [Meziche], and others in my family. I didn’t care about what he said about Afghanistan or America or Palestine.”

Fazazi had grown up in a family whose views were just as conservative as her husband’s. Her father was a firebrand preacher from Morocco who served as an occasional visiting speaker at al-Quds, and whose visits to Hamburg had inspired him to serve as a matchmaker between his daughter and future son-in-law. Her brother had traveled to Afghanistan to live under the Taliban, and he was living there when the 9/11 attacks occurred. Her first marriage, in Morocco, was to another deeply conservative man, one who became so disappointed upon learning that Fazazi had given birth to a daughter that he griped openly about it on the day of the girl’s birth. He decreed that his daughter would attend school for only four years — long enough to learn to write her name. The girl, he said, should be married by age 14.

At first, Fazazi saw her divorce and later marriage to Meziche as her escape, but after arriving in Germany, she found herself surrounded by religious fundamentalists who insisted on keeping her within the fold. At the mosque, she listened as other women debated the merits of female circumcision, a practice some recommended to safeguard what they described as the virtue of their German-born daughters. Beyond this, the conversation each week revolved around a single topic: jihad.

“From dawn we would be listening to jihad chants, until evening,” Fazazi said. “All day long, and no matter what you were doing — eating, putting on clothes — no [part of] life was accepted unless it was dedicated to jihad — to the death.”

Meziche, meanwhile, was hatching plans to put words into action. He talked about moving to Afghanistan and told Fazazi she was obliged as his wife to go with him. Then, with the United States edging closer to a military invasion of Iraq, he talked about fighting Americans there instead. Fazazi argued with him for months, telling him that he would surely be killed, condemning his family to a life of poverty.

“If you want to go, then go,” she finally said one day. The next morning Meziche was gone. He left no clue about his travel plans, or how he might be reached. He also left her no money, so Fazazi was left to rely on government assistance to cover the rent and buy food for herself and her daughter.

Yet, after his departure, she felt strangely relieved. It was almost exhilarating. Soon it occurred to Fazazi that she was free to leave the house, and to go wherever she wanted. And so for a solid month, she went everywhere.

“I put my daughter in the baby stroller and went to the city center,” she said. “Had lunch at a restaurant. Sat in coffee shops. I was truly happy. I felt for the first time in my life that I was free.”

It didn’t last. One afternoon, about four weeks after her husband’s departure, the door buzzer sounded.

“Salaam alaikum,” came the male voice through the intercom. Peace be with you. It was Meziche, back home again after trying unsuccessfully to secure passage to Iraq.

He moved his bags back into the couple’s apartment. Immediately, Fazazi’s outings stopped, and her life returned to the way it had been. Yet Meziche was mulling plans for his next attempt at becoming a militant. He was not yet finished with the idea of “resistance.” And neither was his wife.

A winter rain was tamping down the dust along western Iraq’s Route 19 when Staff Sgt. Ronie Huddleston climbed into his Humvee’s gun turret for what was, according to the day’s mission log, a routine supply run. The planned route from his forward operating base to Kirkuk was just 60 miles, but it required traveling on roads that were pocked with craters from countless roadside bomb explosions. Huddleston’s platoon would be hit 30 times by the mines that soldiers called IEDs, or improvised explosive devices. But on a day as raw and damp as this one, perhaps the insurgents would choose to stay inside and let the convoy pass. Huddleston, in his body armor and Kevlar helmet, rested his palms on the .50-caliber machine gun’s twin grips as the vehicles roared out of the base and headed north.

One of the senior noncommissioned officers at the base, Huddleston, 32, did not normally ride in the gunner’s turret, a place that, in Iraq, was regarded as a convoy’s most dangerous post. But with one of his crew members sick, he decided he would do the job himself. It would give him a chance to keep an eye on his “boys,” the 19- and 20-year-old grunts who served under him. A veteran of the first Iraq war in the early 1990s, he was 10 years older than most of his charges, and he treated them with a father’s tough love. He grieved deeply for each one he lost to snipers or IEDs.

“Every night, with every prayer, it was: ‘If you take someone, don’t take them. Take me,’ ” he said.

As the convoy bumped along, he scoured the terrain for signs of disturbances that might point to a hidden bomb. So far there were none, though the danger would be greatest closer to Kirkuk. Huddleston had imagined he would be on missions like this after the 9/11 attacks, and even welcomed the idea. On the day the planes struck the World Trade Center, he was already 10 years into his Army career, and part of a small unit that carried out covert missions in hot spots around the world, including Somalia. He watched the towers fall from an airport lounge as he was waiting to depart for an overseas assignment. Before he could board, he received a phone call with new instructions from his commanding officer: Go home, repack and get ready.

“I wanted revenge,” he said. “I wish I could tell you something different. We all wanted revenge. Against al-Qaeda, or whoever they told me to take out.”

Within a month, his unit had shipped out to help lay the groundwork for the military campaigns that would soon follow. Then, in early 2003, the Alabama native was ordered to Iraq. The war’s initial phase consisted mainly of lopsided battles against young Iraqi conscripts ill-prepared for the kind of overwhelming firepower that a well-trained and technologically superior American army could deliver. But after Saddam Hussein’s defeat, the uniformed Iraqis disappeared, only to be replaced by insurgents who picked off GIs by ones and twos, and then melted into the nearby desert villages and towns. By early 2004, the number of IED strikes against American forces averaged five per week, and that number was climbing. As security worsened, deployments became more frequent and more prolonged, fraying nerves and straining marriages and relationships, including for Huddleston, who partly attributes two divorces to his long absences from home throughout his Army career.

“You end up seeing a lot of crap,” he said. “You lose guys. Young guys. You start looking around and asking, ‘Why am I here? For what reason, really, am I here?’ ”

As the convoy approached the outskirts of Kirkuk, Huddleston tightened his grip on his .50-cal. The insurgents had observed the American convoys long enough to know the vehicles tended to bunch together as they approached the large traffic circle at the southern gates to the city, forming an attractive target. The GIs knew this, and yet, no one managed to spot the fuel can beside the road with three 120-millimeter mortar rounds wired together inside.

The bomb detonated just as Huddleston’s Humvee was passing, with a powerful blast that crushed the front of the vehicle and flung shrapnel with such force that it sheared Huddleston’s machine gun into two pieces. The pressure wave hurled Huddleston against the turret wall, blew out his eardrums and wrenched his left shoulder so far out of its joint that his arm ended up behind his back. The blast snapped the metal plate in Huddleston’s body armor and split his helmet down the middle, like a cracked egg.

A wild shootout followed, as insurgents briefly raked the stalled convoy with small-arms fire. But Huddleston was out cold and missed all of it. When the other soldiers finally came to his aid, he was lying still, with no detectable pulse. His men were startled when, 30 minutes later, Huddleston abruptly called out and opened his eyes.

“What are you looking at?” he asked of the privates gathered around him.

“We thought you were dead,” came the nervous reply.

But Huddleston was alive, and astonishingly, a check of his body revealed no shrapnel wounds and not even a single broken bone. To the sergeant’s great relief, none of the other soldiers had suffered a serious injury. The brunt of the impact had been borne by the vehicle’s forward armor and the exposed gunner’s turret, where Huddleston, by his own choice, had been stationed.

“That’s why I was the gunner that day,” he mused afterward. “God granted my wish.”

The blast put Huddleston in a fighting mood, and after returning to his base, he refused a medical evacuation to a military hospital. His soldiers helped him pop his shoulder into its socket, and within hours he was back on the job, back at war. He stayed at his base for weeks, insisting on serving out the rest of his regular deployment. “I’ll go home with my boys,” he said.

But he was aware that something wasn’t quite right. Back in North Carolina, his bride-to-be, Elizabeth Park, could sense the change in their phone calls, and even more after he returned home. Normally even-keeled, he was irritable and short-tempered, including with her son — and Huddleston’s soon-to-be stepson — Allan Osborn. Even his handwriting was different. After a battery of medical tests, the couple learned that the blast had caused a severe, yet invisible, wound: internal bleeding that damaged a half-inch layer of brain matter lining the inside of his skull.

Huddleston had come much closer to death than he knew. And, unbeknown to him, he had joined the tens of thousands of U.S. veterans of Iraq and Afghanistan who would be diagnosed with traumatic brain injury, a condition so common among this cadre of warfighters that experts would later call it the “signature wound” of those wars. The damage is often permanent, and studies would associate it with a range of mental illnesses and dysfunctions, including a sharply higher tendency to commit suicide.

Huddleston never returned to Iraq after the diagnosis. He stayed in the Army for four more years and refused to let anyone call him disabled. But the injury had changed him forever.

On a July afternoon in Kabul, Hina Shamsi and a group of human rights lawyers sat across a table from Mehboob Ahmad, a 35-year-old driver from the city of Gardez in eastern Afghanistan. It quickly became clear — to the initial bewilderment of his interlocutors — that he was bothered by the water bottles on the table, as he glanced anxiously at them. When asked, he explained that his American captors had used bottles just like them as instruments for inflicting pain. “He had been forced into stress positions using heavy water bottles and held for hours,” said Shamsi, who would later hear similar stories from other former detainees. “He looked at the water bottles and it took him to a bad place.”

The stories that Ahmad told over the hours that followed were difficult to hear. According to his account, described by the lawyers in legal filings, Ahmad got into trouble because of his boss, a local strongman and police chief who had helped the Americans liberate Afghanistan from the Taliban, but then became embroiled in a violent dispute with a rival warlord. The chief’s enemies accused him of being part of al-Qaeda, so he was arrested and put in a detention camp, along with Ahmad and others in his entourage. Ahmad was held at various prisons while his American handlers sought to squeeze him for details about al-Qaeda connections he swore never existed.

According to the court filings, Ahmad’s captors kept him shackled for hours in painful positions, sometimes suspended by his arms while his feet barely touched the ground, or dangled upside down on a chain, or manacled to a wall with his outstretched arms weighted with heavy water bottles. He described electric shocks, severe beatings and weeks of blindfolding. He told of how his interrogators used dogs to frighten and harass him, and how, during one session, he was forced to lie naked and blindfolded while his captors ran an object across his back and told him it was a snake. The Pentagon at the time denied the claims, although an Army investigation would later lead to criminal convictions for U.S. soldiers accused of using some of the same abusive tactics in two Afghan prisons. Ahmad’s captors ultimately found no grounds for charging him, and after five months, they let him go.

To Shamsi, Ahmad’s debriefing was an excruciating ordeal. But as the investigation led to other former detainees — Afghans, Iraqis and, later, North Africans held at Guantánamo Bay in Cuba — she would hear the same kinds of stories again and again. A common thread in the earliest days of the investigation was the shock described by many of the interviewees at discovering that the brutal treatment was being meted out by U.S. soldiers.

“They would talk about how they might have expected torture and abuse from the Saddam Hussein regime, or one of the warlords, but they hadn’t expected it from Americans,” she said. “I heard that over and over. It really stood out for me.”

Even as a young girl observing the United States from the outside, Shamsi was often struck by the contrast between the idea of America and the confusing reality she saw in the news. A Pakistani banker’s daughter who attended schools in Hong Kong and southern Africa, she read with admiration about the U.S. Constitution and the protections enshrined in the Bill of Rights, but then she would watch with dismay when U.S. leaders seemed to betray the country’s democratic ideals, by supporting the pro-apartheid regime in South Africa, or supplying arms to dictators in Latin America. She regarded America as a land of promise, flawed but striving to live up to its ideals, yet since 9/11, it seemed to her that U.S. leaders had lost sight of what made the country distinct and worth emulating.

“If you’re a student of American history, you don’t wear rose-tinted glasses,” she said. “I knew the United States had not been perfect. But this was so different.”

Her first opportunity to observe American society up close came as a foreign student and freshman at Mount Holyoke College in Massachusetts, where she was warmly welcomed by classmates and teachers. After graduation, she attended law school and was then snatched up by one of New York’s top-rated law firms, Cleary Gottlieb. By 2001, still shy of her 30th birthday, she was working as a litigator in an office just across the street from the World Trade Center.

On Sept. 11, she left her apartment for work a bit later than usual after staying up the previous evening to finish a legal brief. She was on a bus bound for Lower Manhattan when she learned of the first plane attack. Traffic quickly snarled, so she got out of the bus and began walking back toward her apartment, occasionally glancing behind her at the iconic twin skyscrapers, now spewing black smoke. Moments later she watched in disbelief with dozens of strangers as the South Tower disappeared in a pall of dust and smoke.

At one point, someone in the crowd said something about “Muslim terrorists.” Shamsi, a Muslim, suddenly felt strangely conspicuous.

“I was just frozen there, just watching and not knowing,” she recalled. “It’s hard to describe the swirl of fear and concern. And then also just feeling uncomfortable in my own skin.”

A few months later, she volunteered to help with pro-bono cases on behalf of victims of the attacks. But she was drawn increasingly to events outside the country. In early 2002, the George W. Bush administration created a military prison at Guantánamo Bay, and soon photographs and leaked reports raised serious questions about possible violations of U.S. and international law. The camp’s nearly 800 detainees were not technically prisoners of war, but a mix of terrorism suspects, captured combatants and hundreds of others who were turned over by Afghans and Pakistanis in return for cash bounties. Many would face indefinite detention without formal criminal charges or trials, in violation of a basic human rights tenet for which the United States had long advocated in countries around the world. Vice President Richard B. Cheney spoke of needing to work the “dark side.” Then came waves of reports — often backed by photos and official testimony — of abuse and even killings of detainees at military prisons in Afghanistan and Iraq. Americans also learned of CIA “black site” prisons where agency officers tortured detainees, including with waterboarding, and of the practice known as “extraordinary rendition,” in which CIA operatives abducted terrorism suspects and delivered them to countries known to engage in torture.

“I was following all of this and trying to understand, just as a private person who cares about these things,” Shamsi said. “There was a growing sense that there was something deeply, deeply wrong in the [U.S.] response. On the one hand, we have American values: America doesn’t torture or ‘disappear’ people. And yet, on the other hand, there’s the evidence, right before your eyes.”

And so Shamsi took a leave of absence from her company, and months later she quit Wall Street for good. She had no experience as a human rights lawyer, so she worked at first without pay. She commandeered a desk at the New York Bar Association’s office and spent months poring over documents and case files, extracting the small details that might be useful in a future court fight. Eventually, her experience as a litigator attracted the attention of Human Rights First. She joined the group’s legal team and was soon traveling to the Middle East and South Asia to meet with the plaintiffs in Ali v. Rumsfeld, a civil case that sought to hold top Pentagon officials accountable for abuses in U.S.-run military prisons.

Not all her new clients were initially welcoming. The men she encountered bore deep psychological scars, as well as physical ones. Some regarded the American lawyers at first with skepticism and even anger. But eventually the stories poured out.

“Every single person was traumatized, and they all had their own ways of dealing with it or expressing it,” she said. “But they wanted to tell their stories. They wanted accountability.”

They would get none from Ali v. Rumsfeld. Two years after the lawsuit was filed, a U.S. District Court in D.C. would dismiss the case. In his decision, the judge described the mistreatment of Ahmad and the other plaintiffs as “appalling” and an “indictment” of the government’s handling of detainees in its custody. But he concluded that U.S. constitutional protections did not apply to foreigners such as Ahmad, and that, in any case, the law specifically shielded Pentagon officials from civil liability for actions that were within the scope of their official duties.

Afterward, the lawyers faced the difficult task of explaining to Ahmad and their other clients the complex legal rules that caused their case to fail, even though the facts were never credibly disputed.

“In the early years, even when you’re cynical about what the judicial system can provide, there was still a belief about how things are supposed to work,” she said. But now “an American court had sided with the government and denied the accountability that they were looking for.”

It was bitterly disappointing. But it also was just one case, and one round in a long struggle. Shamsi was just beginning to fight.

Six years after his injury in Iraq, Ronie Huddleston’s life had spiraled downward to such a low that he now perceived only one logical path for himself. He prepared carefully. He waited for a moment when his wife and kids were away. Then he picked out the gun and grabbed his phone so he could make one last call, to alert the emergency dispatcher to send out a police patrol. He wrote a note and placed it in a spot where it would be easily found, but not so close as to risk becoming splattered. He eased into his favorite recliner, pistol in hand, and sat for a long moment in the stillness of the empty house.

For years, frustrations and disappointments had settled on him like carrion birds. After 9/11, Huddleston had found a new purpose in helping his country defeat its perceived enemies. He had gone to war eagerly and fought bravely. But the logic of the war had become murkier, making it ever harder to justify the deaths of his “boys.” The injuries from the IED explosion were more profound than anyone had realized at the time. His left arm and hamstring muscles had been badly banged up, resulting in multiple surgeries and chronic pain. His brain injury scrambled his memory and left him so short-tempered that he fought with random strangers over traffic disputes and squabbled constantly with his wife and children. His stepson Allan Osborn, now on the cusp of adolescence, frequently bore the brunt of his wrath. Meanwhile, the Army appeared less interested in him once it was clear he could no longer deploy abroad to fight, and after he received his discharge, he struggled to find meaningful work elsewhere.

Often, his thoughts turned to suicide, and when that happened, he would hear an inner voice egging him on. Why didn’t you just die in Iraq? it would ask.

“You’re a failure as a soldier. You’re a failure as a man because you can’t take care of your family, because you’re all jacked up and cut up so you’re sitting on your ass all the time,” the voice would say. “The kids are scared of you, walking on eggshells because of the crazy guy in the basement. You might just as well go ahead and just do the best thing you can do and remove yourself from them.”

Huddleston was preparing to put the gun’s muzzle in his mouth when the front door abruptly opened. His wife had changed her mind about an errand and had come home early. Seeing what he was doing, she immediately raged at him, kicking the recliner so hard that her husband fell onto the floor. When things calmed a bit, they talked.

Huddleston agreed to counseling, and for a time, things were mostly better. But the strife at home — and especially between Huddleston and his stepson, Allan — never truly dissipated. One day, Elizabeth Huddleston learned about an unusual program that was designed to help veterans and their families work out their problems together, as a unit. It was called Project Sanctuary. If the Huddlestons were accepted, Ronie, Elizabeth and their children would stay at a private mountain retreat for a week, dividing their time between fun activities and intensive, professionally led family therapy. Elizabeth Huddleston completed the application and paperwork, and to her delight, the family was accepted.

Huddleston went along on the retreat, but under protest. Project Sanctuary’s founder and chief operating officer, Heather Ehle, could sense his discomfort from the first moment.

“Ronie was the angry veteran,” she said. “He kept his cowboy hat on and his arms folded. He had a scowl on his face the whole time. My team would get together every morning and it would be, ‘What in the world do we do with that one?’ I just decided to give him a wide berth.”

In one of the retreat’s therapy sessions, each of the children was asked to draw a portrait of his or her family. Allan, then a young teenager, went to work with his pencils and crayons, and soon managed to capture the household dynamic as he experienced it. He drew the family house, and he included images of his mother, his sister and himself. Then, representing his father, he drew flames and smoke coming from a window in the basement.

“That was the one that really kicked me in the gut,” Ronie Huddleston said. “He drew this beautiful picture. There’s his mom, his little sister, him, sunshine, a beautiful house. And there was the basement window with a bunch of scribbling in black and red. Guess where I was.”

“At the time, I didn’t let anyone know that I was paying attention, but I observed everything,” he said. “When I got home, I finally was able to think about what was going on at my house, and about my own responsibility. It was my epiphany. And things started to get better after that.”

Huddleston was so grateful for Project Sanctuary’s impact on his family that he ended up becoming involved, first as a volunteer who helped cook and drive, and then ultimately as a mentor, sharing his experiences with other veterans. One day, after speaking to a group about suicidal depression and his struggle to become a better parent, he was approached by a young veteran from Texas with an unusual request. The man’s name was Carlos Villarreal and, like Huddleston, he had been wounded by an IED explosion in Iraq. Villarreal, the father of two daughters, had struggled emotionally after his return, and he had decided that he would kill himself.

As the two talked in Huddleston’s cabin, Villarreal reached into his pocket and pulled out a .45-caliber bullet. His plan, he said, was to use this very round on himself, someday, when the moment was right. Huddleston’s story had forced him to reconsider the costs. A good soldier never deserts his comrades in battle. To abandon one’s wife and children would be even worse.

He placed the bullet in Huddleston’s hand. “I don’t want this now,” he said. Huddleston accepted the shell solemnly and put it in his pocket.

After the retreat ended, the Huddleston and Villarreal families got into their separate cars and, for a while, traveled along the same highway on their way home. As they were driving through a stretch of desert, Huddleston motioned to Villarreal to pull over. Then the two veterans got out of their cars to talk.

“I don’t like that bullet,” Huddleston said. “It’s an evil bullet, and I don’t want to keep it.”

Huddleston by habit carried a pistol in his car. Grabbing the gun, he gestured to Villarreal to follow him. After they walked for a bit through a desolate field, Huddleston handed the pistol to his new friend.

“Load up that damn round and let’s get rid of it,” he said.

Villarreal chambered the bullet, pointed the gun toward a mound of dirt, and squeezed the trigger. The sound of a single shot echoed through the empty hills. Then the two walked back to their cars together.

Huddleston and Villarreal remained friends. Months after their shared moment in the desert, the two decided to commission a tattoo that both would have engraved on their arms. The inscription reads: “One life saved, one life justified.”

A 110-story skyscraper made of concrete, glass and steel had collapsed on top of Genelle Guzman, yet she had come out of it with relatively minor injuries. Her survival was impossible. It strained belief. From the moment she was pulled from the rubble and into the sunlight on Sept. 12, Guzman had concluded that her salvation was simply, and literally, miraculous. And that belief served as a kind of guidestone for how she would live out the balance of her life.

People who experience similar ordeals often suffer from a kind of “survivor's guilt,” vexed by the seemingly random turns of fortune that spared them while taking the lives of so many others. Not Guzman. Her survival, against all odds, was a divine gift, not to be squandered.

Guzman had grown up going to church in Trinidad, but the free-spirited young woman who moved to New York in 2000 was not especially religious. Her plans to become a professional dancer or singer had derailed, so instead she organized her life around outings to New York nightclubs. She spent nearly every weekend on the dance floor, hoping that her skills would attract the attention of a talent scout or producer. She had a steady boyfriend, a daughter from a previous marriage and a temp job at the World Trade Center’s Port Authority office, a position that paid the bills while she considered possible routes for extending her expired U.S. visa.

Twenty-seven hours in the rubble transformed everything. In her prayers, as she lay pinned inside a small crevice in the broken concrete, she pleaded for rescue, and she vowed to change her life if she lived. Then, around 9:15 a.m. on Sept. 12, her first prayer was answered in the form of the strong hand that grabbed hers from the other side of the debris pile. In the story she would tell later, she heard a man’s voice saying, “I’ve got you, Genelle. My name is Paul, and you’re going to be okay.”

It took an eternity, it seemed, to free her body, as rescue workers had to work carefully to remove steel and concrete without sending more rubble crashing on top of her. Once at the hospital, Guzman faced weeks of surgery to repair her crushed legs. Her doctors warned that she might lose her left leg, which had suffered traumatic tissue damage. Yet, the leg healed after multiple operations, and soon she was able to walk normally, with only a slight limp. Her medical exams revealed the existence of two serious conditions that had previously gone unnoticed: a heart arrhythmia, severe enough to cause fainting spells, and an abnormal growth on her cervix that frequently develops into cancer. Undetected, either might eventually have killed her. Instead, they were spotted and treated during her hospital stay. Guzman learned that her 9/11 injuries possibly saved her life.

When she was finally discharged six weeks later, Guzman set out immediately to honor the promises she had made. That same week, she and her boyfriend, Roger McMillan, rode together to City Hall to get married. She called the pastor of a local church she had visited and asked to be baptized.

Guzman already had achieved minor celebrity status as the “last survivor,” and her story and photograph appeared in newspapers and TV shows across New York and around the world. Within a year, she had received U.S. citizenship and an elaborate wedding ceremony sponsored by a bridal magazine and aired on television. Although inexperienced as a speaker, she began to talk at churches and conferences about her spiritual journey. Often, her testimony included the story of “Paul,” the man who had called her name and held her hand in the rubble. After her release from the hospital, she had tried for weeks to find Paul so she could thank him. She asked visiting city officials and firefighters who he was. No one seemed to know.

Guzman became convinced that Paul was a supernatural being: a real angel who had held her hand and called her name as she prayed for rescue. In 2011, as the country prepared to mark the 10th anniversary of the attacks, she wrote a spiritual memoir about her 9/11 experiences, describing in detail her encounter with Paul. The book was titled “Angel in the Rubble.”

Just before the book’s release, Guzman and her co-author, a Kentucky writer named William Croyle, heard separately from two men who said they knew something about Guzman’s rescue. Both were emergency workers with New York’s fire department, and both had been among a group of first responders who found a young woman trapped alive in the debris of the North Tower on the morning of Sept. 12, 2001. One of the men described holding the woman’s hand as she was freed. His name was Paul Somin.

Croyle flew to New York to meet with Somin and hear his story. Somin had arrived at Ground Zero early on Sept. 12 for a second day of searching for survivors. His unit’s commander had decided that the best place to look was around the remains of a partially collapsed stairwell where a few firefighters had been found alive the day before. Somin and his colleagues found their way to the stairwell and climbed inside. Then Somin discovered the remains of an elevator shaft and decided to yell into it. To his surprise, he heard a faint reply, unmistakably female.

“Help me, help me!” the voice said, according to Somin’s account, later confirmed by New York Fire Department officials.

“What’s your name?” he yelled back.

“We’re not going to leave you, but I can’t see you,” Somin shouted. For a long time, Somin and others from his unit picked their way across the mountain of debris, trying to pinpoint the source of the cries. Finally, Somin decided to ask the woman to try to help.

“I said, ‘Can you stick anything out of the rubble?’ ” Somin recalled in an interview. “And literally right in front of us, she stuck her arm up. And I grabbed her arm.”

Croyle, impressed by the story, immediately arranged for a meeting between Guzman and Somin. The rescue was no less miraculous, but this was a real person who had been there that day. Here, quite possibly, was the real Paul.

Guzman agreed to the meeting and, with her husband, graciously greeted Somin and listened to his story. Yet, when it was over, as she related afterward, she was not convinced that it was the same Paul she remembered from the day of her rescue. If it truly was the same Paul, why had he waited so long to introduce himself?

The two had no further contact after that. Somin was surprised by Guzman’s skepticism, but decided not to dwell on it. Soon afterward, he retired from the fire department and moved out of state.

“Was she lucky? Yeah, she was lucky,” he said of Guzman. “But there was nothing random about our search that day. We went to that spot for a reason. And the reason was that we knew other people had survived there.”

Guzman continued to reflect on the meaning of “Paul.” Was he an angel? An angel in the guise of a New York rescue worker? Something in between?

After a while, “I stopped thinking about it, because the mystery is too much,” she said. “Things happen in your life for a reason, and I just trust, and let it go.”

“Angels do exist. Paul was my angel,” she said. “That was the miracle I was praying for.”

In the early months of President Barack Obama’s first term, U.S. officials added an unusual entry to the government’s “hit list” of terrorism suspects targeted for capture or killing overseas. The man was Anwar al-Awlaki, a well-known and highly skilled al-Qaeda propagandist living in Yemen. Like others on the list, Awlaki had been deemed a threat to Americans. Unlike the rest, he also was a U.S. citizen.

A secret operation was approved, and on Sept. 30, 2011, a pair of drones fired missiles at a vehicle in Yemen’s northern Jawf province, obliterating the car and killing Awlaki and another U.S. citizen who happened to be with him. Two weeks later, missiles struck again in Yemen, this time killing Awlaki’s 16-year-old American-born son — an unintended victim, U.S. officials would later say — and several others.

Obama went on television to hail the senior Awlaki’s death as a “major blow” in the long battle to defeat al-Qaeda. But were Americans safer? Hina Shamsi, studying the details of the attacks from her New York office, was skeptical. The human rights lawyer perceived a different kind of threat in the secret war playing out in the harsh Yemeni desert: a dangerous erosion of one of the most basic protections conferred by the U.S. Constitution. Awlaki had not been tried in a court, yet the U.S. government had acted unilaterally as judge, jury and executioner. Shamsi would play a lead role in one of two lawsuits over the killings, this one filed on behalf of the grandfather of Abdulrahman Awlaki, the 16-year-old victim, a boy who had been born in Colorado and liked playing video games.

“The killings violated fundamental rights afforded to all U.S. citizens,” said the lawsuit, naming senior defense and intelligence officials as plaintiffs, “including the right not to be deprived of life without due process of law.”

At the time, Shamsi was eight years into her new career as a human rights lawyer. She had recently been hired by the American Civil Liberties Union and was quickly becoming one of the group’s premier national security attorneys. Her job sometimes required her to represent individuals accused of engaging in acts of violence, as enemy combatants in Afghanistan or the Middle East, or perhaps even as terrorists. But Shamsi was not a defense attorney. In her cases, it was the government’s behavior that was on trial.

Before the 9/11 attacks, it was difficult to conceive of a time when the U.S. government would assert a right to create secret enemies lists and carry out targeted killings in countries overseas, using pilotless warplanes. Ten years later, the use of drones to eliminate terrorism suspects in remote provinces of Yemen and Pakistan had become so commonplace that the strikes barely made the news.

Republican and Democratic administrations alike would embrace the practice, while refusing to acknowledge it publicly. Members of Congress mostly fell into line; color-coded threat warnings and occasional headlines about terrorist plots created a self-renewing political incentive for aggressive action to prevent a new attack on the homeland. Drone warfare became another permanent fixture in the post-9/11 security landscape.

Shamsi understood the gravity of the al-Qaeda threat, having been an eyewitness to history’s deadliest terrorist attack on U.S. soil. But who, within the government, she asked, was deciding which suspects would live, and who should die? And based on what evidence? The traditional method of stopping terrorists involved arrests, criminal charges, extradition and prosecution.

“We were trying to get basic transparency about something that is deeply chilling, which is the United States claiming secret legal authority to kill without oversight and accountability,” she said. “But the debate too often turned into dances on the head of a pin, over definitions of imminence or self-defense. In the public imagination, it’s the 'worst of the worst’ who’s dying. But it’s all secret.”

Shamsi helped draft a major United Nations study on targeted killings that concluded that the use of lethal drones in circumstances other than an actual war was “almost never likely to be legal.” And after armed drones killed Awlaki’s son, she joined colleagues in drafting the lawsuit against Obama administration officials whom the suit accused of violating the youth’s constitutional rights.

Back at home, Shamsi found that her arguments made people uncomfortable, and even angry. She was accused of undermining a counterterrorism operation that enjoyed broad support, one that U.S. leaders insisted was achieving success. At a conference attended by military officials in Rhode Island, one critic stood up to denounce Shamsi and her colleagues as “human rights-niks” who were “threats to the civilized militaries of the world.”

The criticism at times felt personal, but Shamsi and the other lawyers on the team would not back down. The principles of due process and equal protection, enshrined in the Constitution and the United Nations’ Universal Declaration of Human Rights, were worth defending, even in a time of fear.

“For me, America is a promise that you work toward,” she said. “America has never fully lived up to its values, from the original sins of enslavement to what we did to native populations. And we were so wrong, in a generations-defining, cataclysmic way, after 9/11, when genuine, understandable fear and cynical fearmongering led to a belief that America was entitled to do whatever it needed to do for its own security. And this has moved us further and further from that promise.”

The Awlaki case was never brought to trial. A federal judge dismissed the lawsuit in 2014, in a complex ruling that concluded, in essence, that U.S. military and intelligence officials could not be sued for carrying out duties that were part of a congressionally authorized, White House-approved global war against a dangerous terrorist group.

Many Americans were untroubled by the ruling, and unfazed by the news of deaths in faraway northern Yemen. Awlaki was a self-declared enemy of the United States and he was accused of participating in plots aimed at killing Americans. Yet, it was also true that, in acceding to the use of lethal drones to destroy suspected enemies in countries with which the United States was not at war, Americans had tacitly approved their government’s claim of an expanded new authority: one that allowed it to carry out extrajudicial killings in secret — including, potentially, against civilians and even U.S. citizens — by invoking national security. Future administrations would not easily relinquish that power. Shamsi worried that Americans would one day regret having allowed it to happen.

Raymond Pfeifer resisted wheelchairs for as long as he could, refusing to accept the idea that he was too weak from cancer to get around on his feet. But on the day he finally acquired one — a motorized scooter, donated by friends — it was as though he had been granted a kind of superpower.

Whirring through the hallways of the U.S. Capitol, the veteran firefighter discovered that members of Congress could no longer avoid him. He could outrun the most fleet-footed House aide, and he could maneuver his chair to corner a senator in an elevator or corridor. Smiling from his seat, smartly dressed in his blue New York Fire Department uniform, he all but dared his quarry to try to walk around him, or to refuse to make eye contact.

At the time, a small band of New York first responders was waging a years-long struggle to win congressional approval for medical screening and compensation for rescue workers who became ill because of their work at the plane-crash sites in New York, Virginia and Pennsylvania. The Zadroga Act, the compensation program signed into law in 2011, had expired, and 9/11 workers and their allies had reunited to lobby for an extension. It was a difficult fight, as some in Congress balked over the program’s costs. But the supporters had a pair of aces: comedian Jon Stewart, whose presence helped guarantee media attention, and the indefatigable Ray Pfeifer.

“He got in that wheelchair and went from being Lovable Ray to being a gladiator,” said John Feal, a retired construction worker and friend of Pfeifer’s who helped organize the lobbying effort. “That wheelchair made him the face of the movement.”

The source of his stamina was a mystery, even to his family and close friends. After his cancer diagnosis, he underwent nine surgeries, including one to remove a kidney and another to replace a cancerous leg bone with a steel rod. Then he suffered a heart attack, which forced him to finally retire. But Pfeifer had a well-earned reputation for physical toughness, dating from his earliest days as a young smoke-eater charging into burning tenements across Manhattan. And he seemed to draw boundless energy from his new mission: fighting for benefits for families of 9/11 first responders who died — including the widow and children of Steven Mercado, his comrade who had swapped shifts with him — and also those who became injured or ill after working at Ground Zero.

“He would say, ‘I’m not leaving until this gets done,’ ” his wife, Caryn Pfeifer, remembers. “It was all about his guys, and their widows.”

His teenage son Terence tried to convince him to skip the D.C. visits as his illness advanced.

“You know, Dad, you just went down there,” Terence Pfeifer would say. “You’re not feeling that good.”

Pfeifer would laugh it off and get in the van with the others.

“But I’m the poster boy,” he would say.

A sudden setback with his health nearly stopped him from returning to Washington as the lobbying campaign reached a crucial point. As the Zadroga Act’s benefits were expiring in the fall of 2015, the steel rod in Pfeifer’s leg snapped, leaving him in severe pain and unable to walk. He called his friend Feal, who was then in Washington, to say that he was done. It was one of the few times that Feal heard him cry.

“I wish I was there,” he said. “I let you down.”

On Dec. 3, 2015, the first responders gathered in Washington for a fresh attempt at lining up sponsors for their legislation. Pfeifer, rejuvenated now that he had his scooter, joined them, and soon was given a chance to demonstrate his new potency as a lobbyist. Stewart was standing next to Pfeifer when the group spotted Sen. Rob Portman of Ohio outside the congressional cafeteria. Portman had refused to back the bill, insisting on the need for budget cuts elsewhere to pay for it. The firefighters felt he had snubbed them during a visit to the Republican’s office the previous day. Pfeifer decided to give it another try.

“He set that wheelchair into a gear that I’ve never seen before,” said Stewart, describing the incident at a memorial service years later. “It was like the thing was a funny car. It just took off, and he corners this guy from Ohio.”

Stewart and others repeated their pitch to Portman while Pfeifer sat in his chair, nodding and occasionally chiming in, never yielding as much as an inch of space that might have given the senator a chance to slip away. “He didn’t have to show histrionics. He didn’t have to yell. He didn’t have to scream,” Stewart said. “He sat, his body becoming as big as a boulder, and people wouldn’t get by until they looked him in the eye. And it was magic.”

Portman agreed that same day to become a co-sponsor of the legislation, which extended benefits for victims and families for 75 more years. The measure was incorporated into the 2015 omnibus bill and passed into law two weeks later.

The money allocated for the measure still was insufficient to cover the projected future costs, and Pfeifer continued to lobby for a permanent source of funding. But within a year of the encounter in the Capitol, his health deteriorated to the point that he could no longer make the trip to Washington, even with his wheelchair. In the spring of 2017, he was admitted to a hospice facility. Stewart, who had become a friend, caught up with him by phone a few days before he died.

“How are you, man?” he asked.

“I can’t complain,” Pfeifer replied. “I’m a lucky guy.”

Three days before Pfeifer’s death, his son Terence told his father that he had achieved a high score on the New York Fire Department’s entrance exam and was being offered a position.

“Congratulations,” Ray Pfeifer said. “You’re going to be a fireman.”

On Feb. 12, 2018, Naamen Meziche appeared before a French court to face charges that he had helped plan terrorist attacks in Europe. He pleaded not guilty but was convicted and sentenced to 18 years. The verdict completed a 180-degree turn in the personal fortunes of the French Algerian and his estranged wife. Sixteen years earlier, before the 9/11 attacks upended the couple’s world, it was Mariam el Fazazi who had lived as a virtual prisoner, unable to leave her apartment or socialize without her husband’s permission. Now Meziche was in prison, and Fazazi, for the first time in her life, felt truly free. She had an apartment and a job that paid the bills for herself and her children.

Fazazi took no pleasure in her ex-husband’s hardships, but she eagerly embraced the new life she had created. “I always wanted to get out of that extremist world, even when I was a little girl in Morocco,” she said. “But I couldn’t. I wasn’t able to stand on my feet alone.”

The change, as she recalled, had come slowly at first, and then all at once.

Meziche’s failed attempt to enter Iraq in 2003 had attracted the attention of German police. Shortly after his return to Hamburg, a half-dozen plainclothes officers showed up at the couple’s apartment to conduct a search. They seized computers, files and videotapes and took Meziche in for questioning.

Fazazi’s family, meanwhile, faced similar pressure back in Morocco. After a wave of coordinated suicide bombings killed 33 people in the coastal city of Casablanca, the country’s police rounded up suspected al-Qaeda sympathizers, including Fazazi’s brother and her preacher father. The fiery imam Mohammed el Fazazi was notorious in Europe and North Africa for his sermons urging Muslims to embrace violent jihad. Charged with contributing to the radicalization of the Casablanca bombers, he was found guilty and sentenced to 30 years in prison — effectively a life sentence for the 54-year-old man.

Back in Germany, Meziche was becoming weary of the constant surveillance. He also was increasingly pulled by a perceived obligation to help other Islamist militants he had met on his journeys, Fazazi said.

“How can we sit here eating while our brothers are dying?” he would ask his wife.

Finally, Meziche decided to quit Germany for good. He left the apartment in 2009, initially claiming that he was going on a religious pilgrimage to Mecca. But from his phone calls to his wife, it appeared that he was on the move: first in Iran, then in Pakistan, then in the tribal region between Pakistan and Afghanistan. He never explained what he was doing, but he made clear that he wasn’t planning to return any time soon.

“There’s no way back,” he told his wife in a call.

Fazazi had heard enough. She delivered an ultimatum: Return home within a month or agree to a divorce.

“He answered, ‘Go ahead and file for divorce,’ ” she said. “That’s what I did.”

Meziche never came home after that. Fazazi later learned that he had been arrested in Pakistan, and that a police raid had discovered explosives and guns in his house. Meziche was extradited to France.

For Fazazi, life as single mom was a struggle at first. She had no job experience and a limited social network. Yet eventually she was able to find work, helping with Arabic translation at a German nonprofit that dealt with refugees. “It was the first job I had in my whole life,” she said.

Other changes followed. The days when she skipped wearing her head covering came more frequently. One day she put it away, for good. She saw nothing wrong with head coverings, but for her it never felt like a choice.

“I was about to start a new job and I just decided not to put it back on,” she said.

Fazazi worried at first about her family’s reaction, especially back in Morocco, with its conservative culture. Her father was back at home now, having been granted an early release from prison, and he appeared to have undergone a transformation of his own. After receiving an official pardon from Morocco’s king, Mohammed el Fazazi had publicly renounced violent jihad. Yet, despite the changes she saw, Fazazi worried that her father would be offended by her rejection of conservative Muslim dress, and view her decision as a betrayal of her family.

She decide to broach the subject at a safe distance, in a text message.

“I decided to take off the veil,” she wrote. “I am starting a new job. I have to support my children. I don’t think I can do this job with the veil on, and I don’t want to wear it.”

The message was met with silence. Several days passed. Then, one day, her phone’s texting app chirped. It was a note from her father.

“You’re a grown-up,” it said. “You need to do what’s best for you.”

The short text was liberating, a final psychological break from the past. A few months after the exchange, she decided to go into business for herself. The immigrant who departed Morocco knowing barely a word of German launched a new company that helped German firms comply with government covid-19 restrictions. If things went well, Fazazi thought, she might expand into the nonprofit world, perhaps with a support group for Muslims who struggled to come to terms with their sexual orientation. In the meantime, the job was enough to support a son and two daughters, both of whom were preparing for professional careers. The girls, like their mother, no longer wear head coverings, although Fazazi said she would not mind if they chose differently.

Her transformation had not come without pain. Her relationships with siblings and other close relatives had become badly strained, and some of her old friends no longer associated with her. Yet, to her delight, she has grown closer to her father, who truly had emerged from prison a changed man.

As Mohammed el Fazazi later explained it, his extremist views began to soften after a chance meeting in prison with a female human rights activist who was fighting to improve conditions for detainees. The woman, a Moroccan named Assia el Ouadie, didn’t practice the same kind of Islam he did. Yet she exuded a personal decency and compassion that impressed him. Even though she was around the same age as Fazazi, he and other prisoners called her “Mama Assia” as a sign of their admiration. It was the start of a period of introspection that intensified as he got to know other men who were confined with him. He met prisoners who supported the Islamic State and were quick to condemn anyone who disagreed with them. Others were quietly pious, rejecting violence in any form. Still others just wanted to return to their families and live normal lives.

After his pardon and release, the imam gave interviews in which he disavowed his extremist past. The reaction within militant circles was harsh. The Islamic State issued a death threat. He was denounced as a traitor by radical clerics, including several newcomers who broadcast hate-filled sermons from European cities, as he had done years earlier. The elder Fazazi listened to their messages with concern, worried that the same cycle of radicalization that he helped nurture 20 years ago was starting up again.

But with prison behind him, he was mostly preoccupied with trying to right past wrongs. After mending his relationship with his daughter, he decided that he wanted to travel to New York. In the unlikely event he was granted a visa, he said, he would like to visit the memorial where the World Trade Center had stood.

“I will go in a heartbeat. I will definitely visit Ground Zero,” he said. “It is a very … emotional place.”

The men who flew airplanes into the buildings had believed they were acting righteously, as martyrs, Fazazi said — partly inspired by words he once uttered, but now rejects.

“This is not Islam,” he said. “Heaven is not for terrorists. Heaven is for good people, people who respect life, people who do good.”

Throughout his 20-year military career, Ronie Huddleston guided scores of young Army recruits — his “boys” — on the path to becoming professional warfighters. He never expected that his own stepson would be among them — a second generation from the same household deployed to the Middle East.

When Allan Osborn began talking about a possible military career as a high-schooler, Huddleston assumed that his stepson would apply to the U.S. Air Force Academy, just up the road from their house in Colorado Springs, to study engineering and earn an officer’s commission.

“Dad, I’m not going to go to college,” he said, according to Huddleston’s memory of the conversation. The stepfather began to object, but then stopped himself and decided to just listen.

“I don’t want to go to the Air Force. I want to go Army infantry,” he continued. “And I want to do everything you did, but better.”

Both parents continued to argue for officers’ school, but their son had made up his mind.

“He’s going to do this with us or without us,” Huddleston finally said to his wife. “I don’t want him seeing a recruiter without me being there. I’d rather support him through this.”

Osborn enlisted in the infantry and sailed through basic training. At the time, a U.S.-led military coalition was battling the Islamic State, the Iraq-based al-Qaeda offshoot that had seized huge swaths of Iraq and Syria. Army units were being deployed to both countries to support local forces.

Osborn’s unit soon shipped out to Iraq. A few weeks later came the startling moment when the young soldier called his father to let him know where he was: in the same forward operating base in western Iraq where his stepfather had served years before.

Huddleston was incredulous at first, and a bit worried. Later, as the news settled in, he just felt angry.

“It’s ridiculous. This needs to be over with,” he said. “I fought there. And now having a son fighting the same freaking war, standing on the exact same freaking dirt I had stood on … ” His voice trailed off.

“‘Forever wars,’” he said, “are not the answer.”

Photo editing by Karly Domb Sadof and Olivier Laurent; text editing by Peter Finn; design and development by Garland Potts; copy editing by Annabeth Carlson and Martha Murdock.