Is there such a thing as a benign dictator? Can a ruthless but rigorous autocrat offer the best medicine for a country rebuilding after a catastrophe? How does one weigh human rights abuses against the record of a seemingly well-run economy in a troubled region? And, most of all, how forgiving should we be of an authoritarian government if it took office after a genocide it helped to end?

For nearly 30 years Rwanda’s president Paul Kagame, the puritanical former rebel leader who seized power after the 1994 genocide, has faced these questions. In the intervening years not only has his image broadly survived, but he has been at the centre of a global personality cult. US administrations and UK governments have lavished attention and aid on his regime. He has been lauded as a new model leader. His Rwanda has been depicted as an African Singapore or even a Switzerland.

Now, in the form of a devastating book by Michela Wrong, comes something of a reckoning — or at the very least a reassessment. Do Not Disturb is a damning j’accuse on many fronts. An extraordinarily brave piece of reporting, it draws on years of work in the region, including for the Financial Times, and primarily on the accounts of Rwandans who were once close to Kagame but have fallen from favour.

Among many allegations that will embarrass the UK Foreign Office and others involved in the Commonwealth heads of government meeting in Rwanda’s capital Kigali in June, it charges Kagame with presiding over a murderous network operating out of its embassies aimed at assassinating exiled opponents; he denies the charge. It also challenges the idea of an economic miracle, arguing that the figures are doctored by the state. While both charges have been made before, here they are delivered in relentless detail.

Yet more devastating is Wrong’s dissection of the region’s awful past. She accuses Kagame’s Rwandan Patriotic Front of slaughtering thousands of Hutus as and after they took power. Even more explosive are the claims about who was responsible for the presidential plane crash in April 1994 that precipitated the genocide. The plane in question crashed over Kigali, killing the presidents of Rwanda and Burundi on their way back from agreeing a power-sharing deal with the RPF. For years after the genocide, it was broadly accepted that the jet was shot down by Hutu extremists who had been preparing for the genocide and just needed the spark to be lit. Wrong quotes former RPF insiders who suggest, as others have in the past, that it could in fact have been the RPF.

So how could Rwanda’s western backers have so misjudged their man? Guilt, with a dollop of self-interest, is the reply. Kigali denies the specific charges. It will no doubt seek to denounce them as genocide denial — a criminal offence in Rwanda. But Wrong does not deny the genocide. Rather she is disputing the RPF’s narrative of what happened next, when the genocidaires were finally routed. In doing so she reminds readers that the truth can, of course, prove messy and that just because you have suffered appallingly does not mean that everything you do thereafter is justified. As for the outsiders, including British Conservative and Labour politicians, who have over the years backed Rwanda and broadly shrugged at the critiques, it is, she contends, a case of “Tread softly for you tread on my dreams”.

Of some things there are no doubt. In just 100 days in the spring and early summer of 1994, Rwanda endured the most systematic slaughter of a population anywhere since 1945. More died in Cambodia’s genocide, but that was spread over several years. Over half a million people, mainly from the minority Tutsi ethnic group, but also some from the majority Hutus, were murdered in Rwanda in a spree orchestrated by extremist Hutu groups. What was especially shocking about the genocide was not just its speed but its communal nature. Time and again villager turned on villager, with machete, club or hoe.

Compounding the shock in the west was the realisation that the world’s leaders had not just been slow to respond; they had turned a blind eye. The debacle of the US military intervention in Somalia the previous year and the embroilment in Bosnia had blunted the west’s appetite for intervention. So much for the resonance of George H W Bush’s “new world order” of three years earlier.

Many news organisations also knew they had been slow off the mark. There were exceptions, but many western news editors and Africa-based correspondents were focused on the morality tale of South Africa’s first all-race elections. I was among those who headed north from Johannesburg only at the end of the slaughter. We saw the heaps of bodies, but the guilty had fled or were fleeing to neighbouring Zaire, dropping their machetes at the frontier.

Late one night in early July I remember a New York Times correspondent racing up to a group of fellow correspondents with an account of RPF revenge killings. But the reports drew little attention. When set against the monstrous scale of the genocide, they seemed small-scale. This was also a time when the RPF, with their well-disciplined and often English-speaking cadres, were busily seeking to rebuild the state and promising reconciliation. It was a story that understandably all but the backers of the old guard wanted to believe and it was not wholly unfounded. It also reflected that human urge for hope after such terrible despair.

The author undercuts this post-genocide narrative by telling the story of the RPF through the words of defectors who she has talked to over many years. Her book is shaped around the life and career of Patrick Karegeya, a Rwandan whose career mirrored Kagame’s. Both grew up in exile in neighbouring Uganda. Both backed Yoweri Museveni’s rebel movement that took power in Uganda in 1986. Among the striking anecdotes about Kagame, it emerges that he was then supposedly nicknamed “Pilato” for his reputation as an enforcer who pushed for the death penalty for disobedient cadres — although when in power, he did ban the death penalty in Rwanda.

Do Not Disturb opens with the account of Karegeya’s murder in a swanky Johannesburg hotel on New Year’s Eve 2013. It then sweeps back through his career including his stint as Kagame’s foreign intelligence chief for a decade after the genocide. In those years he helped tiny Rwanda play an outsized role in the region’s convulsions. But he later fell out with Kagame and, after a stint in prison, fled in 2007 to South Africa where he set up an opposition movement before he was found strangled in the Michelangelo Hotel. Wrong chronicles the murder with kaleidoscopic detail. South African police have linked it directly to Rwanda’s government. Kagame has denied this although he has said he wishes it had been.

Kagame’s aides will no doubt dismiss this book as one-sided and reflecting merely the biased view of defectors. Wrong could arguably have devoted more space to the horrors of the genocide, if only to set up what happened next and to exonerate her of the regime’s accusation of being partisan. I also would have welcomed the testimony of some of Kagame’s western backers, although it is possible that they did not want to go on the record. But these are quibbles. This is a remarkable, chilling and long overdue book — and one whose narrative does not bode well for Rwanda’s future.

Do Not Disturb: The Story of a Political Murder and an African Regime Gone Bad, by Michela Wrong, HarperCollins, RRP£20/Public Affairs, RRP$18.99, 512 pages

Alec Russell is the editor of FT Weekend and a former South Africa correspondent

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Letter in response to this article:

Rwanda leader’s cult feeds off country’s past horrors / From Donald WF Conkey, Washington, DC, US