Among the many other war film references listed recently, some work should
(sorry, I meant to say "attention should") be paid to the work of Sam Fuller,
especially THE STEEL HELMET, about Korea--made in 1951 during the war itself--
and CHINA GATE, possibly the earliest Hollywood Vietnam flick (1957), dealing
with the French phase of the struggle, before Dien Bien Phu.  As I recall,
it's sort of a thinking person's GREEN BERETS, with a surprisingly solid
supporting performance by Nat King Cole.  Dalio also has a supporting role.