Contrary to some assumptions, Chaplains in the US military do not exist solely to serve the spiritual needs of American servicemembers.  In fact, they often play a strategic role in a conflict.  From Chaplain (LtCol) Ira Houck:

Chaplains are the religious leaders in the military and religious political leaders in Iraq have respect for the integrity of our office.  It’s because of our position that they will tell us information about their areas of expertise that they wouldn’t share with anyone else.

While the use of Chaplains in these roles has a long history, there is a unique aspect of the cultures currently engaged by the US:

Religion is a big part of Iraqi lifestyle and politics. There is no separation of church and state here.

Read more at Chaplains provide new perspective on Iraq.