Mosul has fallen. Its residents must not fall with it.

By Sean Callahan

Iraqi government troops, aided by United States forces, have wrested control of most of Mosul from ISIS. Left behind in this city of ruins and beyond are hundreds of thousands of people looking for shelter, for food, for water and for a future. As one displaced person told us recently, It is clear who we have been liberated from; it is not clear to whom we have been liberated.

Iraq in general and Mosul in particular make the case for why the U.S. cannot afford to cut its diplomacy, relief and development funding. The budget request for Fiscal Year 2018 calls for a 37 percent reduction in funding for those critical efforts.

If the budget request is approved it could cost our country more money in the long run. Diplomacy and development are necessary to secure the peace, and contain conflicts before they spiral out of control--leading to expensive military engagement and displaced communities requiring emergency humanitarian spending. It is a very literal case of a stitch in time saving nine or 900 down the line.

Diplomacy means that the U.S. must help negotiate a government framework agreeable to authorities in Baghdad and in the Kurdish areas. Inclusive local governmental structures must be established that are trusted by people on the ground and that protect minorities. International support and attention is critical. This is the nitty-gritty work of diplomacy. Succeed and displaced people may return home. Fail and they will continue to flee or look for other options.

Relief, reconstruction and development are also needed to help families rebuild their lives and to support communities as they repair and replace infrastructure demolished by the fighting. No one is going to move back to Mosul without hope for rebuilding. Help from the United States and the rest of the international community is critical to that hope. Innocent Iraqis caught in the middle need to know that the world cares about them. We must stand in solidarity with them as we expect them to do with us when terrorists strike.

At Catholic Relief Services (CRS), we are familiar with this situation from our experience on the ground. Since 2014, Caritas Iraq and CRS have been providing assistance to hundreds of thousands of those displaced by ISIS -- Christian, Yezidi, Sunni, Shia and Turkman Iraqis. We are currently scaling up our assistance to those who have recently fled Mosul.

The liberation of Mosul and surrounding communities from ISIS must not be in vain. Intense and sustained diplomatic activity is needed to ensure that Iraq provides security and respect for all of its citizens regardless of religion or ethnicity. And relief, reconstruction and development is needed to enable Iraqis to create sustainable communities in the wasteland that ISIS has left behind.

Sean Callahan is president and CEO of Catholic Relief Services, the official overseas humanitarian organization of the Catholic community in the United States.