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In Stanley Kubrick’s “Full Metal Jacket”, an American soldier indiscriminately guns down Vietnamese civilians from the helicopter. Did this kind of blatant killing of civilians happen in the war? Was this scene accurate?(r/AskHistorians)
This scene is taken almost verbatim from a passage in Michael Herr’s Dispatches. Herr worked as a freelance journalist writing primarily for Esquire magazine (and later served as an adviser for Kubrick). Whether or not this event actually occurred is unclear, as Herr himself has admitted that portions of Dispatches are apocryphal rather than strictly factual.
Such events did, however, occur, and with more regularity than the U.S. would like to admit. Deborah Nelson, a Pulitzer Prize-winning journalist, cataloged hundreds of such events in her book The War Behind Me, which was based on U.S. military documents which were accidentally declassified and then hastily reclassified.
There were also two significant citizen/veteran organizations that presented testimony describing wartime atrocities. These are Wikipedia entries, but both are well-sourced (the latter, for example, provides a link to the full testimony given by veterans), and offer several avenues for further online reading:
Lest my post become an accidental indictment of American helicopter crews of the Vietnam War (which was a very dangerous job – the U.S. lost thousands of helicopters during that war), I would note that it was a helicopter crew that prevented the My Lai Massacre from being bloodier than it already was.