I think it's unfortunate that in the dozens of American movies about Vietnam, the South Vietnamese are portrayed at best as nothing more than cardboard cutouts, as mere scenery. Worse than "forgottten," their story is completely nonexistant.
There were of course many instances of South Vietnamese dishonoring their own soil and nation, but those are hardly the only stories.
From 1965 to 1975 - and much more so thereafter - the South Vietnamese lived in a veritable horrorshow, a nightmare. I'm amazed that in 27 years no filmmaker has seen fit to tell that story. Maybe Tony Bui will do it someday.