Civilizations collide when the transcendental values that govern them are used to define identity. During the Crusades, the Christian belief that God was immanent in the person of Jesus Christ collided with the Islamic vision that God is transcendent. For the Christian world all that was holy and venerable was embodied in the Cross of the Holy Sepulcher on which Jesus is believed to have been...

Like a benevolent mother opening her arms to all the children in the neighborhood, Africa held its arms open for successive waves of refugees from Arabia. In turn, the immigrants brought with them the light of Islam and shared it with the people of Africa. This was the quid pro quo between Africa and Arabia: Africa gave protection to the Arabs. In turn, the Arabs shared their faith...