Tripoli fell in August 2011, and Muammar Gaddafi was captured and killed near Sirte soon after, ending more than four decades of his rule. Fifteen years on, the people who might have built whatever came next are, in significant numbers, somewhere else.

Al Jazeera has spoken to some of them, and what they describe is less a flight from danger than a slow calculation about the future.

Two departures

Sarah Mizran is 32, an architect, and lives in London. Her account is not about what she escaped but about what her leaving means in aggregate. "Libya loses more than just skills when young professionals leave," she said. "It loses a sense of possibility when an entire generation grows up feeling that they have to leave in order to build a future, and that leads to a loss of hope in the country itself."

That is the mechanism that makes a brain drain self-sustaining. Each departure is individually rational and collectively corrosive, because the strongest argument for staying is other people staying.

Nader Elgadi is 36 and ran his own media company in Tripoli before he moved to Britain. He was not poor and he was not desperate, which is what makes his account useful. "I went from running my own business and living comfortably in Libya to starting my life from scratch in the UK," he said. "The first two years were really hard." In 2018 he founded a charity, Libya in the UK, for people making the same transition.

The politics behind it

Libya's trajectory after 2011 did not follow the pattern its returning diaspora expected. Tarek Megerisi, a visiting fellow at the European Council on Foreign Relations, described what happened to that first wave of returners: "After the revolution there was a mass return of Libyans from all across the world," he said, but the new authorities "basically just acted like Gaddafi's government did."

The second collapse came in late 2014, when fighting broke out around Tripoli's airport and the country entered its second civil war. The division that followed has not been resolved. Megerisi's summary of the present arrangement is bleak and quotable: "Pity the country that has two governments and nobody interested in governing."

Toby Chitayat, an associate at the British risk consultancy CRI Menas, is also quoted in the reporting on the country's condition.

What would bring people back

Mizran is not writing the country off, and her condition for return is specific rather than sentimental. "A sense of stability in the country will prompt a stronger wave of the diaspora wanting to return," she said.

Stability, in that formulation, is not a synonym for peace. It means being able to plan: to sign a lease, hire staff, take a mortgage, enrol a child in a school that will still exist in five years. Those are the things a divided state cannot underwrite, and they are the things a 32-year-old architect needs before she moves back.

She also said something that complicates the neat framing of exile. "Home is not something we find once and keep forever," she said. "It's something we create again and again."

What we do not know

There are no numbers here, and that absence is worth stating plainly. The reporting we relied on does not quantify how many Libyans have left, what the unemployment rate is, or how large the diaspora has become, and we have not supplied figures from elsewhere that we could not check. What it offers instead is testimony, which is evidence of a different kind: several people, asked why they went, giving the same answer.