Unlike poor Mrs. O'Leary's Chicago cow, there is apparently no one to blame for the great 1973 fire at the National Archives and Records Center's Missouri cite housing its miltiary records. The National Personnel Records Center in the St. Louis suburbs housed veterans records for millions of men and women who had served their country in numerous branches and government work.
Only 20% of the Army records spanning 1912 to 1960 remained and only about 30% of the Air Force records survived from 1947 to 1964. Millions of records were destroyed ruining the chances of family historians, veterans, and others to access crucial validating records of service.
The lack of a clear cause (it was suggested the files had spontaneously combusted) left the field open for conspiracies aplenty.
The less than stellar performance of the government in exposing soldiers and airman to radioactive fallout after WW2 was just breaking in the news. With the threat of thousands - if not millions - of veterans falling ill with potentially related diseases...and suing the government...a fire was carefully engineered to erase the evidence.
The full military records of alleged presidential assassination, Lee Harvey Oswald, were also destroyed in the fire. This has fueled the fire for some conspiracy buffs. If his record supported some versions of the story they would implicate government and/or other collusion in the event. This could not happen so a fire was set.
What is known is that millions of Americans had to struggle to piece meal together records to verify service. Countless others searching for some small tibit of knowledge about a hero of a conflict in order to learn something of where they come from and what their ancestors did, were unsuccessful.
The individuals who found, retrieved, cleanup, and researched an alien craft (ala Roswell, NM) were on the verge of being discovered and so a fire destroyed the public records of this service while maintaining the private and classified records housed elsewhere.
Destroying, and endangering the lives of many people nearby, one file would unlikely have been the target.
The Great File of 1973 was a blunt force blow to the history of the men and women who sacrificed, suffered, and sometimes died for their country.