Here is some interesting history regarding US efforts to locate and identify WW II missing service personnel:
At the war's end, American casualties remained unaccounted for around the globe, some where they had fallen, some in the depths of the oceans, and many in temporary cemeteries scattered throughout the world where battles occurred.
Following the war, the United States (U.S.) Government launched a global initiative called, "The Return of the World War II Dead Program," to locate aircraft crash sites, comb former battlefields for isolated graves, and disinter temporary military cemeteries around the globe. The U.S. Army created the American Graves Registration Service (AGRS) to perform this task. Once remains had been recovered, they were transported to Central Identification Laboratories (CIL), where technicians confirmed or established identifications of more than 280,000 individuals. The identified service members were then buried according to the wishes of their next of kin. The program operated from 1945 to 1951, working until all known leads were exhausted. The Army program was a worldwide endeavor employing approximately 13,000 personnel, and costing $163.8 million in wartime dollars.
After the end of the official program for returning the dead of WWII, the U.S. Army Mortuary system continued to recover and identify smaller numbers of WWII service members. These identifications stemmed largely from reports of remains discovered by the citizens of the countries where the casualties occurred. Upon receipt of such a report, a mortuary team would investigate, recover, and identify the remains. As a result, more than 200 additional service men were identified between 1951 and 1976.
After 1976, the task of recovering and identifying the remains of WWII service members fell largely to the U.S. Army Central Identification Laboratory in Hawaii (CILHI). From 1976 to 2003, that organization sent recovery teams into the field using anthropologists and odontologists to identify an additional 346 individuals. In 2003, CILHI merged with Joint Task Force-Full Accounting (JTF-FA) to form the Joint Prisoner of War/Missing in Action (POW/MIA) Accounting Command (JPAC). JPAC accounted for an additional 300 individuals.
In 2003, historians at the Defense Prisoner of War Missing Personnel Office (DPMO) began to develop a comprehensive database of WWII service members whose remains were not recovered or identified after the war. This database was a significant step in creating a comprehensive plan to research WWII missing personnel.
Historians from DPMO were primarily responsible for answering questions from family members about missing service members from World War II until January 2010 and the passage of the National Defense Authorization Act (NDAA) 2010. Responding to this law, the Department of Defense expanded World War II accounting efforts to more proactive case development. Historians and analysts at DPMO collaborated with JPAC in researching, investigating, and nominating for recovery the cases of U.S. casualties still missing from WWII.
In 2014, the Secretary of Defense directed that DPMO and JPAC, along with the Life Sciences Equipment Laboratory (LSEL), be merged to form the Defense POW/MIA Accounting Agency and reach full operational capability in January 2016.
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Defense POW/MIA Accounting Agency > Our Missing > World War II