Amid Niger Coup, Nigeria Grapples with Potential Military Intervention

When President Bola Ahmed Tinubu of Nigeria took the helm of the West African regional bloc of countries last month, he thundered before a roomful of his presidential peers that he would show no tolerance for military coups in an area that had faced five in less than three years.

“We will not allow coup after coup,” he said, drawing a round of applause.

Two weeks later, mutinous generals took power in neighboring Niger, prompting Mr. Tinubu and the regional bloc, the Economic Community of…