In the summer of 2017, a Chadian spy called me from a military base in the capital, N’Djamena, to inform me of a rebellion brewing to the north. The rebellion itself was hardly news—there have been scores of failed coups in Chad since it gained independence from France, in 1960—but the spy surmised that this revolt might come to pose a real threat to the regime. It was lead by Timane Erdimi, a disenchanted nephew of the President, Idriss Déby, who had seized power in 1990 in the same fashion as each of his predecessors: by capturing the Presidential palace in a rebellion of his own. For weeks, Erdimi’s rebels had been amassing weapons and personnel in the lawless desert of southern Libya. “Some soldiers are loyal to the President, some soldiers are not—no one knows how this will develop,” the spy told me. “They’re far from N’Djamena, but who knows how long that will remain true.” Now, on a hot summer night, he continued, Déby was deploying military and intelligence officers on an aerial surveillance mission. Their task was to photograph the rebels’ positions, and to assess their numbers and capacity. The sound of revving airplanes drowned out the end of the call.

In the following weeks, there were several indications that things were getting worse, although there was no conclusive reporting on the rebellion itself. In late August, Déby severed relations with Qatar and expelled its diplomats, and reporters speculated that this act was in political solidarity with various Arab nations that, months earlier, had accused Qatar of supporting terrorism; in fact, the spy said, it was because Chadian forces had found evidence that Qatar, where Erdimi lives in exile (and from where he has remotely directed the rebellion), was providing cash and equipment to the rebels—an explanation that I was unable to verify, but that better fit a terse public statement, issued by Chad’s foreign ministry, calling on Qatar to “stop all activities aimed at destabilizing Chad.” In September, the spy reported that some Chadian élites had quietly left the country, out of fear that they would be detained for their past ties to Erdimi. Then, in October, Déby withdrew hundreds of Chadian soldiers from Niger, where they were fighting Boko Haram as part of a multinational African counterterrorism task force, which is backed by Western countries, including the United States. Chadian officials refused to offer an explanation, and reporters implied that Déby was reacting to his country’s inclusion in President Trump’s travel ban. Not so, said the spy; Déby needed the troops at home to defend his northern border. The spy noted how hastily—in the absence of official information, and in a country without a free press—Western outlets had filled in gaps with lazy geopolitical narratives, without pursuing explanations that would involve an African government having domestic motivations of its own.

That fall, I set about trying to verify the existence of the rebellion. There were a few ambiguous reports of skirmishes near the Libyan border, but they usually sourced back to social media. Meanwhile, the spy kept sending grim updates. In November, he told me that there were dozens of wounded and dead soldiers in the military hospitals and the morgue. “The rebels are advancing,” he said. But, when I called an American official who was based in Chad, he wasn’t sure what to make of the spy’s uncorroborated reports; it was possible that there was a rebellion, he said, but something of this scale had never come up in his meetings with Chadian military brass. His uncertainty raised uncomfortable questions: If the state of the rebellion was as the Chadian spy had described, how could the United States not know? And, if military clashes had taken place, was the Chadian army using training and equipment that it had solicited from Western militaries, under the guise of counterterrorism, to quash Déby’s political opponents?

The rebellion carried on mostly in the shadows. Last August—roughly a year after the spy’s phone call from the military base—Reuters reported that a “fledgling rebel movement” of forty-five hundred fighters had attacked government forces near the Libyan border. (The Chadian government denied that any fighting had taken place.) Meanwhile, the rebels took hostages, posted photos of themselves carrying surface-to-air missiles, and threatened to topple “Idriss Déby and his international backers.”

Then, earlier this month, after the rebels breached the Chadian border, France’s Air Force spent four days bombing rebel convoys. For years, the French military has used its base in N’Djamena as a staging ground for air strikes against jihadis in Mali, as part of Operation Barkhane, its campaign against terrorism in the Sahel. But this was different: an intervention on behalf of an aging autocrat, carried out “to prevent a coup d’etat,” as the French foreign minister put it. More significant, it was a tacit admission of how little progress has been made—that, after decades of supporting Sahelian strongmen, and turning a blind eye to their abuses, Western countries have been unable to devise any regional strategy except one that conflates the strength of a regime with the stability of a country, and which brings about neither stability nor strength.

No Chadian President has survived on his own. Since Chad gained independence, the French have traditionally supported whoever is in power until the moment that rebels overrun the capital and the President flees or is killed. There has never been a change to the Presidency by free or fair election, only succession by capture the flag; N’Djamena falls and the victor holds the Presidency for as long as he can. (Last year, as Déby approached the end of what had been his final constitutionally permissible term, Chad’s parliament revised the constitution to allow him to retain the office until 2033.) During the Cold War, the C.I.A. went tit for tat with Libya’s strongman, Muammar Qaddafi, in sponsoring whichever Chadian warlord most vehemently strove to oust the one backed by the other, human rights and the rule of law be damned. In 1987, President Ronald Reagan welcomed Hissène Habré, then the Chadian President—who had held French tourists hostage, murdered thousands of dissidents, and tortured detainees by forcing them to suck on the exhaust pipe of a running car—to the White House, and called it “an honor and a great pleasure to have had him here.” Military support that ought to have been ruthlessly conditional instead allowed men like Habré to be conditionally ruthless. The result was that Chad and its neighbors never developed functional institutions, and most Sahelians derived no benefit from the existence of the state. In 1990, fifteen per cent of Chadian babies died before their first birthday, and the average citizen lived to age thirty-nine.

France and the United States have typically prioritized short-term, tactical advantages in their approach to fragile African states—the limiting of Soviet influence, for example, or the maintenance of access to profitable mines. But these are meaningless objectives in the face of impending catastrophe. The Sahel is being ravaged by climate change, leading to drought, starvation, and mass migration. At the same time, the region is experiencing a demographic explosion; countries that have more than doubled in population in the past few decades are expected to double again in the next twenty years. Add these factors to the status quo of the least educated and least developed region of earth: nonsensical borders, terrible colonial history, corrupt governance, joblessness, hopelessness, and a population bereft of food and rights and dignity. Six decades of the West gently prodding authoritarians toward democratic reforms has done little to achieve them. Presidential elections serve more to obscure the lack of progress than they do to elect a leader, and a lack of free expression has allowed for the region to exist in a kind of information vacuum, limiting both local development and the capacity of Western governments to devise a coherent approach—or, apparently, to stay abreast of Chadian troop movements. As I wrote in this magazine, in 2017, the West’s strategic approach to countries like Chad, to the extent that it ever had one, has been paradoxical: in pursuing stability, it strengthened the autocrat, but in strengthening the autocrat it enabled him to further abuse his position, exacerbating the conditions that lead people to take up arms.