I have traveled the route between Bamako, the capital of Mali, and Mopti, in the center of the country, many times. When I returned earlier this year, the lively towns I encountered in the first 300 miles seemed familiar to me. But in the last 100 miles, to my surprise, we had the road almost to ourselves. I noticed new buildings, military outposts.

This part of Mali is plagued by rising instability. Islamist militants remain active in the region. The armed Islamists who attacked U.S. special forces in Niger in 2017, killing four soldiers, came from this area. They have recruited some Fulani people, which has triggered the Bambara and Dogon to organize self-defense forces, kindling tit-for-tat ethnic violence.

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