The following photographs contain disturbing content. They show people whom Human Rights Watch understands to have died in the custody of the Syrian government, either in detention facilities or after being transferred to a military hospital.

—The Editors

The war in Syria is an ongoing humanitarian catastrophe; it represents, too, the greatest political failure of the past decade—one that historians might well come to regard as the shame of our generation, for Westerners and Middle Easterners alike. Despite its savagery, the war has been extensively—though, critics say, ineffectively—documented in still photographs, videos, films, and on cellphones. This criticism rests on a misunderstanding of the relationship between photography and politics—a relationship that has been romanticized since Robert Capa and his comrades went to Spain, and that led to some of Susan Sontag’s sharpest insights in On Photography.

For eight years, the world has watched as the forces of a criminal butcher, President Bashar al-Assad, have bombed, raped, tortured, displaced, and murdered millions of their countrymen, women, and children. They have repeatedly used chemical weapons against civilians and created what Michael Young, a Lebanese journalist, has called “a humanitarian crisis of biblical proportions.” The country’s physical infrastructure—schools, hospitals, cities, towns, farms, marketplaces, water and electricity supplies—has been destroyed; so have its human relations and social fabric. An untold number of people, but probably more than 100,000, have been imprisoned in torture chambers. An even greater number have lost limbs, eyes, minds. The massacres that took place last year in Eastern Ghouta have been compared to those of Srebrenica during the Balkan Wars; “the violence is relentless and unbearably cruel,” a columnist for The Guardian wrote. A generation of children has been left traumatized, unschooled, orphaned; one trembles to think of the vengeance they will wreak.

The Syrian war has been called the death of liberal, or humanitarian, or democratic interventionism, the cause that Sontag and others vociferously championed in Bosnia; of international solidarity; of the responsibility to protect. The problem, though, is that Syria is not Bosnia (or the Spanish Civil War). The forces that Sontag lauded in Bosnia—the forces of democracy, secularism, religious tolerance, and multi-ethnic citizenship—are hard to find in the Syrian conflict. Tragically, the butcher is opposed by an equally heinous array of forces, including but not limited to al-Qaeda, al-Nusra, Ahrar al-Sham, and ISIS. Addressing this situation, Radwan Ziadeh, a prominent Syrian opposition activist, wrote, “Imagine how it feels to know your country is run by a terrorist regime and [by a] terrorist organization—the worst terrorist regime and the worst terrorist organization.” Damascus is not Sarajevo.

Of course, many Syrians do adhere to democratic values; they have bravely risked, and lost, their lives in pursuit of them. But values and a realizable political project are not the same; as Michael Ignatieff wrote in 2013 in The Boston Review, “The Syrian opposition has failed in making their cause a universal claim.” Richard Falk, a scholar of international law, has similarly noted, “Anti-Assad forces have been unable to generate any kind of leadership that is widely acknowledged either internally or externally; nor has the opposition been able to project a shared vision of a post-Assad Syria.”

The war in Syria has been much more dangerous to document visually than the one in Bosnia, since photojournalists (and journalists) in the former have been targeted, tortured, and murdered at unprecedented rates by all sides. Nonetheless, a wide array of photographs has been taken, and distributed, by everyone from amateur civilians under siege, using their cellphones, to professional Western and Arab photographers. In Regarding the Pain of Others, Sontag wrote that photographs of war “show how war evacuates, shatters, breaks apart, levels the built world.” This is certainly true of the Syrian photographs (see, for instance, the images that The Guardian ran in February of last year).

The traditional hope of photojournalists was that, in revealing the cruelty of war, the world would take what Martha Gellhorn had called “saving action.” But in this war, the perpetrators themselves—both in the Assad regime and in the terrorist groups opposing him—have photographed, indeed advertised, their own atrocities, of which they are apparently proud. So while documentation of war crimes is still vital, the classic function of photography is now sorely tested. Perpetrator photographs were made infamous by the Nazis and Khmer Rouge; in the early twenty-first century, they have made a startling resurgence. Much of what we know about ISIS’ atrocities comes from its own propaganda videos: images such as the beheadings of journalists and other hostages, and the burning alive of a Jordanian pilot, have been seared into memory.

The Assad regime, too, has created irrefutable evidence of its crimes, though these images may be less familiar. This is the subject of Operation Caesar: At the Heart of the Syrian Death Machine, by Garance Le Caisne, an independent French journalist who has been reporting in the Middle East for the past three decades. Originally published in France in 2015, the book has been translated into Dutch, Polish, Italian, German, Spanish, Finnish, and Romanian. In Germany, it won the prestigious Geschwister-Scholl Prize, which honors moral and intellectual courage. Here in New York, I have yet to meet anyone who has read it.

“Caesar” is the codename of a man who worked as a military-police photographer—that is, a government photographer—in Damascus. (Today, he lives under witness protection somewhere in Northern Europe.) Before the war, he photographed crime and accident scenes: car crashes, suicides, fires. But as anti-Assad protests erupted in the spring of 2011—peaceful protests, in which “Dignity!” was the first demand—Caesar’s work, and his life, changed. He was not particularly political, but “one day,” he told Le Caisne, “a colleague told me we were to photograph some civilian bodies.” Though described as terrorists, they were actually ordinary people from Deraa, where the first, peaceful protests spontaneously broke out after a group of schoolboys was arrested, and subsequently tortured beyond recognition, for the crime of writing anti-government graffiti. The bodies of the protesters that Caesar saw that day had been desecrated by soldiers, though the dead did have names. Soon, the corpses would be “just numbers.”

The protests continued; the bodies piled up; Caesar’s work became more gruesome. “I had never seen this before,” he recalled. “Before the Revolution, the regime would torture people to extract information. Now they were simply torturing people to death. I saw the candle burns… Some people had deep knife wounds, eyeballs ripped out, broken teeth, whip marks… There were bruises filled with pus… Sometimes, the bodies were covered in blood, and the blood was still fresh.” Each body was carefully photographed several times: one picture “of the face, one of the whole body, one from the side, one of the head and shoulders, one of the legs.” Every corpse was classified according to which arm of the intelligence services had jurisdiction over the victim in question. Medical examiners would issue a report for each body, typically ascribing the deaths to a “respiratory problem” or “cardiac arrest.”

The process was structured, scrupulous, precise, and hideous. “This time it is the state itself telling the story of the terror it is inflicting,” Le Caisne observes. “As opposed to the amateur films, full of emotion, that the activists for freedom shot in the streets of the cities, these official documents chill the blood.” In addition to physical agony, the photographs speak of psychic anguish, too. The victims, Caesar said, “knew they were going to die… They had their mouths open in pain, and you could sense the humiliation they had suffered.”

Caesar was aghast at the duties of his new job, and terrified, too. “I had to take breaks so that I wouldn’t start crying… I could picture my brothers and sisters as one of those corpses. It made me ill.” He decided to confide in his closest friend, Sami (another pseudonym)—a conversation, like many in Assad’s police state, that was fraught with danger even among trusted family members. Sami, who worked as a construction engineer in Damascus, had been awakened to the nature of the regime decades earlier, as a schoolboy, when a beloved elderly teacher was arrested, threatened with the rape of his wife, and “disappeared”: “I realized that we weren’t living in a country but in a vast prison,” Sami recalls.

Caesar wanted to quit his job and escape from Syria; Sami urged him to carry on. Working from Damascus for two years, the two friends downloaded 55,000 images of horror, transferred them to memory sticks, and smuggled some of them abroad for safekeeping over the Internet. Some of the photographs were already circulating clandestinely within Syria: “This macabre and secret databank allowed those who had received no word of a brother, a husband, a daughter to receive confirmation of their death,” Le Caisne writes.

A team of about a dozen photographers worked with Caesar. As they printed the photographs, “we couldn’t avert our gaze,” he says. “The detainee came back to life in front of us. We could really see the bodies, imagine the torture, feel the blows raining down. Then we had to write the report.” What does it mean—what toll does it take—to partake in such an enterprise? “We used to say, ‘On the Day of Judgement we will be asked to account for ourselves.’”

Through the testimony of various actors, including Caesar, Sami, doctors, and prisoners who survived, Le Caisne takes us inside the “machinery of death.” There is the transformation of hospitals into torture centers and the hasty sham trials that lead to inevitable guilty verdicts, imprisonment, and torture—and, often, execution. There is the widespread use of starvation within the prisons—due not to food shortages, but as a means of crushing the prisoners’ solidarity (“Hunger destroys all morality,” one observes). Most of all, there is the orgy of unrestrained torture. As one former prisoner puts it, Assad wants not only “to kill his people… by eliminating them physically, he wants to dehumanize them.”