Global gabfests tend to be gloomy affairs these days. Bigwigs bemoan the state of geopolitics, wring their hands over existential risks, urge greater global co-operation—and go home with little to show for it all. The Africa CEO Forum, a gathering that took place on May 16th and 17th in Kigali, the capital of Rwanda, offered a welcome contrast. As bosses, politicians and financiers gathered to discuss the role of Africa’s private sector…