Factual error: The final scene of the movie has Col. Kirby and the little Vietnamese boy supposedly on the beach at Da Nang, Vietnam. Kirby is saying, "The future of 'nam is you, kid", and the camera pans out to the sea and the sun is going down. The sun's sinking in the east...
Suggested correction: Nowhere in the film are we told where in Vietnam the Green Beret base is, just that it is in South Vietnam (of course). South Vietnam has a Western coast, along the Gulf of Thailand, along which anyone can watch the sun set over the sea.
Around the 18:00 - 18:30 mark a character welcomes John Wayne to Da Nang. This base is returned to throughout the film, including the infamous sun setting in the east scene. Da Nang's beaches face to the Northeast. Only when you get south of Nha Trang does the Vietnamese coast begin to offer a south to southwest horizon on the ocean.
Factual error: After returning to camp Savoy 29, Cpt. Nimh states that he wants to go home to Hanoi but first he wants to "kill all filthy stinking cong." The civil war in Vietnam was between the Republic of South Vietnam and the Viet Cong. North Vietnam (the capitol of which is Hanoi) was a separate country that aided the Viet Cong. So even if Cpt. Nimh killed every single "filthy stinking Cong" in South Vietnam, North Vietnam would still be communist, and he still couldn't go home.
Suggested correction: The Viet - Cong were pretty much wiped out during the TET offensive of 1968, North Vietnam won because they out - lasted the U. S and of course were supplied by PEKING and RUSSIA. Afghanistan was lost for very much the same reason, the opposition being supplied by their allies next door, and even though American service deaths had gone down to almost nothing, the U.S. bungled its departure, giving over much material.