Islamist insurgency’s long battle with Nigeria sparks economic downturn, draws neighbor into conflict.

Falling prices of cows and the rising cost of diapers in Chad have turned the tide in neighboring Nigeria’s six-year war with Boko Haram. Rampaging through northeastern Nigeria and attacking neighboring Cameroon in January, Islamist militants squeezed paths used by herdsmen who walk one of Chad’s main exports—cattle—to market in Nigeria. Boko Haram also choked off the flow of manufactured goods into Chad’s capital, N’Djamena. Prices for everyday imports like plastic tubs have skyrocketed. The smothering of trade routes signaled a call to arms for Chad, Nigeria’s landlocked and poorer neighbor. Now its army—among Africa’s most battle-hardened and feared—has been on the offensive in Nigeria, swinging momentum in a conflict that has cost tens of thousands of lives, displaced more than a million people and seen Boko Haram abduct perhaps thousands of adolescents. “We have two main means of access to the sea—one through Nigeria and the other through Cameroon,” said Chadian Brig. Gen. Zakaria Ngobongue. “It’s like we have two nostrils through which to breathe. One is kind of stuffed up. If you stuff up the other nostril, how are you going to breathe?” Chad is likely to leave Nigeria swiftly—as it has done in previous regional interdictions—before getting mired in a protracted counterinsurgency, commanders from African nations say. Some warn that the conflict risks swinging back in favor of Boko Haram after Chad exits. “Nigeria needs to commit and be ready to engage,” said Maj. Gen. Abdelrahman Youssef Mery, commander of Chad’s Special Anti-Terrorist Group.

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