How does a Muslim teenager, raised in California, go from laidback surfer dude to radical extremist?
Iranian-American author Laleh Khadivi sets herself the difficult task of answering this question in A Good Country, the final novel in a trilogy that follows three generations of Kurdish men from 1920s Iran to present-day America.
Tracing the seemingly inexplicable route to radicalisation has become ever more pressing, she says, in a world where young men and women vanish overnight into the ranks of terrorist groups, or turn on their countrymen in sudden, horrific attacks.
Recent terror attacks in London and Manchester were spearheaded by British citizens, while a pre- school assistant became the first Singaporean woman detained under the Internal Security Act for radicalism earlier this month.
"Our world is becoming incredibly fractured," Khadivi, 39, says over the telephone from California, where she is based.
"But if you can portray a human soul going through this transition and engender a kind of compassion via fiction, there is a greater degree of understanding. If we look at each other as monsters, the dialogue is not going to advance and the violence will continue."
Khadivi was born in Esfahan, Iran, and emigrated to the United States as a two-year-old with her family to escape the Iranian Revolution in 1979.
She has no memory of their flight and considers herself "thoroughly hyphenated" as a second-generation immigrant. Yet, from a young age, she was aware of an older inheritance, the Kurdish ancestry rooted in a place she had never been to.
The mother of two, who is also a documentary film-maker, began writing her trilogy 10 years ago with The Age Of Orphans (2009), in which Kurdish orphan Reza Khourdi is enslaved in 1921 by Iranian soldiers and raised to brutalise his own tribe.
In its sequel, The Walking (2013), Reza's son Saladin flees Iran in the aftermath of a political killing and pursues the American dream as an immigrant.
The dense lyricism of The Age Of Orphans, which Khadivi says was drawn from the likes of William Faulkner and Toni Morrison, gives way to a more spare, direct narrative in A Good Country.
Saladin's son Rez is a teenager just getting his first taste of Californian adolescence: surfing, smoking weed and sex. But paranoia seeps into his community after the Boston Marathon bombings in 2013 and Rez slowly finds himself pushed to the margins because of his name and skin colour.
Increasingly able to relate only to other young Muslims, he begins to wonder about a promised place in the Middle East, where people like him can build a new country.
Khadivi describes Rez as somebody "who has a bit of curiosity in him".
She says: "The way I approached it was to chart this curiosity piece by piece, from the point when he didn't even know he was curious, until the circumstances of the world around him made him pursue his questions of belonging."
She hopes young Muslim readers, especially those who live in societies where they are minorities, can see something of themselves in her novel, and of "the struggle to be the other in these difficult times".
As for other readers, she would like them to "put themselves in Rez's shoes and try to understand why, when so many doors are closed to you, you choose to walk out of the building".
She is a staunch advocate of pluralism, the idea that people should live peacefully in diversity, instead of segregating themselves into tribes.
"Pluralism may be a blind hope," she says. "It has yet to be proven possible in our modern times, but we don't have much of a choice."
Rez, and those who choose radicalisation, are "moving back in time".
"But to move forward, we have to take everyone around us as our clan."
•The Age Of Orphans ($17.17), The Walking ($27.92, paperback) and A Good Country ($44.34, hardcover) are available for pre-order from Books Kinokuniya.