Three men water newly planted trees on March 18 in al-Qosh, an ancient Christian village in northern Iraq. The village emptied out last August as Islamic State fighters approached. But the extremists never entered al-Qosh and the village and residents have returned. The men are watering outside a monastery that dates to the 7th century. Alex Potter for NPR hide caption

itoggle caption Alex Potter for NPR

Izzat Ibrahim al-Douri, a former member of Saddam Hussein's inner circle (shown here in 2002), leads one of the Sunni armed factions helping ISIS in its fight against the Iraqi government. Jassim Mohammed/AP hide caption

itoggle caption Jassim Mohammed/AP

Iraq's Prime Minister Haider al-Abadi, speaking Thursday in Washington, said recent battlefield victories showed the Islamic State could be defeated. The extremist group still holds large parts of the west and the north of Iraq. Kevin Wolf/Kevin Wolf hide caption

itoggle caption Kevin Wolf/Kevin Wolf