In his book When Victims Become Killers, Mahmood Mamdani observes that what sets the Rwandan genocide apart from most crimes against humanity of the twentieth century, including the Holocaust, is that it was a “popular” genocide. Over the course of three months in 1994, ordinary Hutu civilians–from farmers to teachers to priests–picked up their machetes and proceeded to help exterminate 800,000 Tutsi fellow citizens and their sympathizers, many of whom had been neighbors, friends and in some instances members of their own families. It is this particularly unsettling aspect of the genocide that led one political commissar with the Rwandan Patriotic Front (RPF)–the Tutsi rebel movement that deposed the Hutu government in the capital of Kigali–to remark, “When we captured Kigali, we thought we would face criminals in the state; instead, we faced a criminal population.”

Jean Hatzfeld’s new book, Machete Season: The Killers in Rwanda Speak, is an attempt to trace what went on in the minds of this “criminal population.” The book revolves around interviews with ten Hutu men serving sentences for participating in the genocide in the region of Nyamata in central Rwanda. Obeying orders given by the local authorities in April 1994, and reinforced by government militias, Nyamata’s Hutu men engaged in the daily slaughter of Tutsis, who had fled to the surrounding marshes for shelter. By the end of the killing in mid-May, all but 9,000 of Nyamata’s original 59,000 Tutsi inhabitants had been massacred.

Predictably, the killers featured in Hatzfeld’s book indulge in a fair amount of evasiveness, tending to minimize their involvement or shift blame onto others. It is to Hatzfeld’s credit that he nonetheless manages to elicit some illuminating testimony from them. The book makes clear that the genocide fed off a deeply ingrained and widespread resentment of Tutsis among Rwandan Hutus, a resentment that, in the months leading up to the genocide, was whipped into a murderous fury by the government’s ceaseless anti-Tutsi propaganda, much of it broadcast on Hutu radio. Hutu animosity toward Tutsis, as one man explains, is practically imbibed with the mother’s milk: “During the dry seasons of early childhood, the Hutu hears grown-ups repeating that Tutsis take up too many plots of land…that those people are too in the way.” The roots of this animosity, however, go deeper than the men themselves manage to grasp. As Mamdani and others have shown, anti-Tutsi prejudice can be traced back to Rwanda’s colonial days, during which time the ethnicities of “Hutu” and “Tutsi” were transformed by the Belgians into political identities that framed the former as indigenous–and inferior–natives and the latter as alien Hamitic settlers. The tragedy of the Rwandan anticolonial struggle is that, while it succeeded in expelling the Belgians, it left their ideological structures intact–most disastrously the binary opposition of Hutu native versus Tutsi settler.

Still, it is one thing to resent, even to hate, Tutsis, another to kill them systematically. Here is where Hatzfeld’s book is most revealing, for it sheds light on an often overlooked or neglected aspect of the genocide–economics. While the killers often insist that the genocide boiled down to a simple choice between killing or being killed, this is only partially true. For once the men began profiting from the genocide–primarily through the cattle, land and property of fleeing or murdered Tutsis–participation clearly evolved into a voluntary activity. Soon enough, as one man states, “we no longer needed encouragement or fines to kill, or even orders or advice.” Once the genocidaires had set the ball in motion, the extermination project found its own economic momentum.

Ultimately, Hatzfeld’s book presents a deeply pessimistic outlook on human morality. Nearly as disturbing as the slaughter that the perpetrators describe is the nonchalance with which they carried it out. Encouraged by the authorities and by their own self-interest, and believing that they would face no consequences for their actions, the men came to thoroughly dehumanize their victims. The very routine of genocide quickly desensitized them into blithe indifference toward the activity of killing. “In the end,” one man remarks matter-of-factly, “a man is like an animal: you give him a whack on the head or the neck, and down he goes.”

A decade after the genocide, resentment and hatred continue to fester in Rwanda. “Everyone is obviously sorry,” one killer tells Hatzfeld, “but most of the killers are sorry they didn’t finish the job.” Another volunteers that there are those who are “patiently waiting for the next opportunity.” The original resentment and hatred that fed into the genocide are now compounded by the fact that Hutus find themselves at the mercy of the very Tutsis they tried to eliminate. Paul Kagame, the man who led the RPF to victory in 1994, thereby becoming the first Tutsi president of Rwanda, has rightly sought to bring perpetrators of the genocide to justice. But he has also invoked the genocide to suppress legitimate criticisms of his regime. Some of the very Hutus who helped the RPF overthrow Kigali’s genocidal government found themselves accused of genocide and bullied into silence once they began objecting to the RPF’s despotism. Eleven years after the tragedy, Rwanda, it seems, is stuck between a rock and a hard place. Between a totalitarian Tutsi regime on the one hand, and the potential of another genocidal Hutu one, prospects of moving forward look bleak indeed.