This week I spoke to Ed West, author of The Silence of Our Friends: the Extinction of Christianity in the Middle East. Ed writes in our cover story about the rise of Christian militias in Iraq after Christians achieved a spectacular victory when they drove ISIS out of the northern village of Badanah.

Since the invasion of Iraq in March 2003 the aftermath has illuminated the complexity of the country's political situation. I rang Ed and asked him to explain what this latest developments in light of the country's recent history.