LAGOS, Nigeria—To understand why Africa's top economy is faltering after five years of Islamist attacks, take a look at Tochukwu Odidigwe's car-parts dealership.
In June, an explosion tore through a traffic jam near his storefront near the port of Lagos, the country's commercial hub. The deadly blast left his street covered in ash and his customers scared to come back. "They are afraid they may be killed," said Mr. Odidigwe.
