In the city of Al-Fashir, Sudan, innocent civilians have been killed in such numbers that blood is visible in satellite images. A video comes from a hospital: dozens upon dozens of civilian corpses, inside and out, and the few survivors who are gasping and have now been executed. Entire neighborhoods leveled, villages erased, and tens of thousands of people dead-by bullets or by hunger in the desert. The Islamist militias have turned civil war into a theater of extermination. In Al-Fashir, Christians have been “hunted down and executed,” explains the NGO International Christian Concern. “They came into our village shouting...