"The international community must respond to the outrages systematically committed by Daesh with a rock-solid resolve to prevent similar future abominations from recurring."

“We have a mission here; we have a mission with the Muslim people. Our Christian community believes in this mission, that we should be ready to stay, to take this responsibility,” no matter the risks.

Christians in northern Iraq try to rebuild their lives after the defeat of ISIS, but the terror of being driven from their homes is not easily forgotten.

Christians are slowly returning to help rebuild northern Iraq, but many remain fearful of an ISIS resurgence and feel abandoned by the national government.

Few Yazidi families have been able to escape from temporary shelters in Syria and Iraqi Kurdistan. Their home villages have not been swept for mines and booby traps left behind when ISIS was dislodged.

Cardinal Parolin said he had seen the most recent video attributed to Islamic State in which the pope and Vatican are threatened.

"I think they have chosen Somalia because there is no central authority," Bishop Giorgio Bertin said.

After surviving ISIS, Christian communities in Nineveh face a new threat as Kurdish Peshmerga forces and Iraqi government troops backed by Shiite militias square off across the province.

About 100,000 Christians -- among them more than 60,000 Syriac Catholics -- were expelled from the Ninevah Plain by the Islamic State group in the summer of 2014 as the militants campaigned to expand their reach into Iraq.

Trying to impose the will of the United States on Iraq (and now Syria) took a deadly toll, killing hundreds of thousands of civilians, destroying much of modern and ancient Iraq, sending into exile millions of refugees—and created ISIS.