So he did. He took the foreign-service exam again, passed, and in 1991 began his training. The following year, he was posted to Riyadh, Saudi Arabia, and every overseas assignment after that was in the part of the world that diplomats call, usually with affection, the Sandbox. He studied Arabic in Tunisia and did tours at the embassies in Cairo and Damascus, and at the U.S. mission in Jerusalem during the second intifada. Even when he rotated back to Washington, his jobs—Iran desk officer, staff assistant in the Bureau of Near Eastern Affairs—usually related to the Sandbox.

It's curious that a kid from California who grew up knowing nothing about the Arab world would come to devote his career to the Middle East and North Africa—as opposed to, say, Asia or Scandinavia or even no particular place. A European woman named Henriette, who met Stevens in Jerusalem in 2003 and had a "fantastic, turbulent" on-and-off romance with him for nine years, tried to explain it to me.

"After we had become a couple," she said, "I asked Chris when was the first time he noticed me with interest. He told me that it was at the dinner party where we first met. He said that he had liked the way I smelled. Chris was a sensualist—he applied all his senses in experiencing the world. For people like us, the Middle East is tantalizing. The smell of coffee with cardamom, and of apple tobacco burning in water pipes; the color and touch of carpets and fabrics; the sounds of the muezzin call to prayers and the energy of crazy urban traffic and large desert landscapes. The warmth of its people and the sound of their music and language. If you combine that with analytical curiosity invested in understanding the long history of the region and the complex dynamics of its current politics, the Middle East is a place you can't resist. It is not only an intellectual endeavor—it makes you feel fully alive."

···

When Stevens and Nathan Tek docked in Benghazi in April 2011, they were greeted by the rebel deputy minister of foreign affairs. Over the next days and weeks and months, the two met with everyone they could: the leaders of the Transitional National Council (the rebel government), shopkeepers, teachers, doctors, militiamen back from the front. "It was like they all spoke from the same script," Tek says. "They were all saying the same things to me: They all wanted a new Libya that represented the aspirations of the people. In my mind, it truly was a popular revolution."

That was a critical message for Stevens to convey to his superiors. Stevens's job, which is every diplomat's job, was to provide reliable information and thorough analysis upon which Washington could formulate policy. Though the United States had already chosen a side in the revolution, opposing a sitting head of state is not undertaken lightly. (Qaddafi, despite being a vicious nut, had been marginally helpful in the so-called war on terror, and Libya has the largest proven oil and gas reserves in Africa.) Had the rebels been less credible—had they, for instance, been unstable butchers likely to plunge the country into bloody chaos for years on end—the calculus would have changed considerably.

"Chris was the single most important voice," says Jeffrey D. Feltman, who at the time was the assistant secretary of state for Near Eastern affairs. "That didn't mean he was the only voice, and it didn't mean everything he said was acted on. But his was the single most important voice."

What made Stevens good at his job was his ability to get people to trust him. That is not something that can be faked: It is possible to manipulate people into confiding in you, of course, but it is not sustainable, especially for an outsider in a foreign land. "He understood," says Tek, "that you have to express empathy in a genuine way. And he defied the stereotype of an American diplomat who was equal parts arrogant and ignorant. He was honest and human.