Not all USA soldiers in foreign wars were delivered back to US soil. A famous example of a overseas cemetery is at Normandy

http://en.wikipedia.org/wiki/Normandy_American_Cemetery_and_Memorial

which is maintained by these guys http://en.wikipedia.org/wiki/American_Battle_Monuments_Commission

As for the actual hands on work for body identification, recovery, and transport, the Graves Registration Service guys were your main unit.

http://www.qmfound.com/graves_registration.htm

http://www.archives.com/experts/holik-urban-jennifer/graves-registration-service-in-world-war-ii-part-i.html

http://www.archives.com/experts/holik-urban-jennifer/graves-registration-service-in-world-war-ii-part-ii.html

Though nowadays it seems to be known as Mortuary Affairs