Boston Marathon

For former friend of Boston Marathon bomber, a burden of shame and betrayal

"Your betrayal broke me."

Youssef Eddafali, whose former friend, Dzhokhar Tsarnaev, was sentenced to death in 2015 for orchestrating the bombing at the Boston Marathon finish line with his older brother, Tamerlan, in Dhaka, Bangladesh on April 14, 2023. Ten years after the attack that killed three people and injured hundreds, Eddafali still wrestles with guilt and anger over the “monster” he thought he knew. Fabeha Monir/The New York Times

BOSTON — Last year, nearly a decade after the bombing at the Boston Marathon, Youssef Eddafali wrote a letter. It had been years in the making, and he agonized over every word, but the hardest thing to figure out was the salutation.

Eddafali, 29, still was not sure to whom he was writing. Was it the friend he had once thought of as a brother, whose journey as a young Muslim immigrant had seemed to mirror his own? Or the calculating killer who revealed himself April 15, 2013, when he murdered and maimed innocent people in the name of the faith they both shared?


In the end, Eddafali concluded it was both, so he split his missive into two parts. The first he wrote to “the old Jahar,” the boy he had known. The second letter was written to a stranger. He addressed it to “The Monster.”

“Your betrayal broke me,” Eddafali wrote to Dzhokhar Tsarnaev, his former friend, who was sentenced to death in 2015 for orchestrating the bombing at the marathon finish line with his older brother, Tamerlan. Tamerlan Tsarnaev died in a gunbattle with police four days later; Dzhokhar Tsarnaev remains on death row.

Three people were killed by the bombs loaded with nails and ball bearings that the brothers had made: Lingzi Lu, 23, a graduate student from China; Krystle Campbell, 29, a restaurant manager from Medford, Massachusetts; and Martin Richard, an 8-year-old from Boston. Seventeen lost limbs and more than 250 were injured in the bombing, which led to a dramatic four-day manhunt that shut down the city; the brothers also shot and killed a campus police officer. An unknown number of spectators, runners and emergency responders still experience emotional trauma from that day.

Another group of people, Eddafali among them, were affected in a different way: They had known Dzhokhar Tsarnaev and considered him a friend. Many were young people in high school or college, on the cusp of adulthood, when the bombing abruptly turned the world they knew into a frightening and unfamiliar place.


Ten years later, as a changed city pauses to honor those who died and reflect on the passage of time, some of those who knew the Tsarnaev brothers still struggle to define how the experience changed them. A decade after they were plunged into guilt, anger, betrayal and shame, they know one thing: There will be no reconciling their before and after, no understanding how or why.

It is a dissonance felt in the wake of every mass shooting, by those who discover to their horror that they know the killer.

“I watch what people say every time it happens — that they had no idea — and I recognize it, because I’ve been there, too,” said Larry Aaronson, 82, who lived on the same street as the Tsarnaev family and taught history at Cambridge Rindge and Latin High School, where Eddafali and Dzhokhar Tsarnaev, known as “Jahar,” graduated.

Cambridge Rindge and Latin High School, where Youssef Eddafali and Dzhokhar Tsarnaev graduated, in Cambridge, Mass. on April 13, 2023. – Sophie Park/The New York Times

There is little research examining the psychic toll on people who had been close to those who kill. The marginality of their position — close to tragedy but connected to its source — can be alienating, stranding them on the outside as their communities gather to heal, and making it feel unsafe or insensitive to discuss their own baffling experience. A dozen people who knew Dzhokhar Tsarnaev declined to speak to a reporter even a decade later, or did not respond to requests for interviews.


“There’s an element of guilt by association, and a weird dichotomy, because the person they knew doesn’t exist anymore,” said Jaclyn Schildkraut, a researcher who has studied mass shootings and is executive director of the Regional Gun Violence Research Consortium at the Rockefeller Institute of Government.

The experience “is like being knocked into a parallel universe,” she added, “and you can’t get back.”

For friends who were also Muslim immigrants, the consequences have been even more jarring.

Eddafali and his family had immigrated to the United States from Morocco in 1999, when he was 6, and he spent years reconciling his Muslim faith with his emerging American identity. A standout basketball player in high school, the boy who had endured ethnic slurs and playground bullying after 9/11 now proudly heard classmates chant his name at games. He found he could navigate fluidly among students of different races and backgrounds, an interlude that felt magical.

“When you found the pocket,” he said of that time, “it was bliss.”

Beside him in the pocket was his friend Jahar, the sociable wrestling team captain who had come to the United States with his family from Kyrgyzstan in 2002, when he was 8, and also knew the challenge and the triumph of acceptance. They had met in middle school, when both were becoming chameleons, Eddafali said, honoring their families’ Muslim faith at home while maintaining separate lives as fully American teenagers.

They trained as lifeguards together, worked together at the Harvard pool, partied with their “boys” beside the Charles River. Both were well liked, athletic, bound for college, examples of the immigrant success story that progressive, multicultural Cambridge loves to tell.


Until all at once, one of them wasn’t.

So unfathomable was Dzhokhar Tsarnaev’s violent turn that many of his friends did not believe it, even when photos of the brothers flooded the media a few days after the bombing.

Small moments in their shared history made the news seem inconceivable. The lunches he bought classmates who were short on cash. The pep talks he gave teammates when they hit the wall. Even in college, where he failed classes and sold drugs, Jahar still encouraged friends, they said, urging one to develop her talent for drawing in art school.

For Eddafali, seeing his friend’s face on TV felt like “10,000 volts of electricity coursing through my body,” he later wrote. He felt unmoored by thoughts of the dead and wounded, and, as the truth sank in, by thoughts of Jahar packing a backpack with explosives and dropping it discreetly on a sidewalk packed with families.

“My trust in other people was shattered,” Eddafali said, “and I couldn’t trust myself, for allowing a sociopath to get so close.”

In Cambridge, where the diverse, ambitious public high school fuels countless American dreams, residents recoiled from the revelation of homegrown terrorism. After Aaronson, still in shock, spoke to reporters about the seemingly sweet-natured teenager he had known, the retired teacher said he felt stung by a disapproving backlash and feared he had sacrificed his reputation.

“I felt like a pariah,” he said. “People wanted to repress it and forget it, and I thought we needed to talk about it. I had such a deep sense of betrayal.”


If much of the city could choose to set aside its tie to the brothers, Eddafali did not have that luxury. The FBI soon came to interrogate the stunned 19-year-old about his knowledge of the bombing. His phone was tapped and his movements tracked, he said. Across Boston and Cambridge, other Muslims also faced renewed suspicion and scrutiny, and continuing surveillance, according to advocates.

Eddafali resumed his studies at Bentley University, outside Boston, in the fall of 2013, but federal investigators came to question him again in November. He appealed to his professors for empathy and flexibility, he said, but failed his exams when neither was granted. His GPA plummeted, and he dropped out of college, amplifying his feelings of shame.

Back at home, he spiraled lower, plagued by depression, anxiety, insomnia, stomach ulcers. Constantly worried that others might find him suspicious or threatening, he stopped wearing backpacks and baseball caps, worn by the Tsarnaevs on the day of the bombing, to minimize any resemblance. He felt just as lost as he had at 7, when he could not find a path to self-acceptance after 9/11.

“The separation between me and the rest of the world was chasmic,” he said.

Years later, he expressed his anger at that damage in his letter to the imprisoned Tsarnaev: “Your actions scorched the blooming trust between Muslims and non-Muslims a decade after 9/11,” he wrote. “You grabbed a branding iron and scarred each and every one of us again.”

Eddafali said he considered suicide, but in time, sought help instead, finding solace in therapy, prayer and meditation, and in taking better care of himself. Someone suggested he try keeping a journal.


As soon as he began to write, in 2015, he had glimpses of clarity, he said, moments when his feelings did not overwhelm him.

It was as if he had been “walking around with an immense weight, and I didn’t know how to put it down.” He filled dozens of pages, energized by a new goal: to tell a different story about being Muslim, in hopes of rebuilding empathy and trust.

“When I put it outside of me, I could observe it in nuanced ways,” he said. “I could release it and go on with my life.”

Others have been moved by a similar impulse. John “Derf” Backderf, a graphic novelist who wrote a book about his high school friendship with Jeffrey Dahmer, who became a notorious serial killer, said he felt driven to explain the staggering impact the revelation of Dahmer’s crimes had on him.

“With the snap of a finger, my entire personal history was rewritten. You can’t imagine how disorienting that was,” Backderf wrote in an email. “What had been a silly and (mostly) fun high school experience was now dark and disturbing.”

Now staying with friends in Southeast Asia while finishing the final chapters of his memoir, Eddafali has a title, a cover and a Kickstarter campaign to fund its production.

Finally looking ahead after a decade, he said he wants to go back to college, finish his degree and pursue a career as a filmmaker. “I had to get back to the person I was,” he said. “But now I’m ready, because now I have a voice.”


He mailed his letter to his former friend last year as another step in his own healing, with no hope of receiving a reply. The convicted bomber has been held since 2015 at a “supermax” federal prison near Florence, Colorado, and is appealing his death sentence for a second time.

Asked if he would have become a writer if he had never known Dzhokhar Tsarnaev, Eddafali grew animated. “No, no, no — hell, no,” he said, eyes wide. “I wouldn’t wish that on my worst enemy.”

Like Backderf, who said he still switches between his original high school memories and the darker “rewritten history,” Eddafali has come to terms with his own parallel realities.

Tracey Gordon, a teacher in Cambridge who remembers Dzhokhar Tsarnaev as a model student in her fifth- and sixth-grade classrooms, put it simply.

“Both things are true,” she said. “We want everything to make sense, and it just can’t.”

This article originally appeared in The New York Times.


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