Question: John Wayne starred in what early Vietnam War film?
About the article "Vietnam War", section "Popular culture".

Candidate passages:
John Wayne began working in films in 1926 as an extra, prop man, and stuntman, mainly for the Fox Film Corporation.
He frequently worked in minor roles with director John Ford and when Raoul Walsh suggested him for the lead in "The Big Trail" (1930), an epic Western shot in an early widescreen process called Fox Grandeur, Ford vouched for him.
Wayne's early period as a star would be brief, as Fox dropped him after only three leads.
He moved over to Columbia Pictures, where he ran afoul of studio boss Harry Cohn.
As a result, Wayne was dropped from leading man to supporting player to bit player and finally down to being an extra again.
After the Columbia debacle, Wayne solidified his stardom – albeit as a minor star – in a string of low-budget action films (mostly Westerns) at Warner Bros. and Universal and the "Poverty Row" studios Mascot, Monogram, and Republic.
Fortunately, Wayne kept on friendly terms with John Ford who, as a result, gave Wayne a career boost with "Stagecoach" (1939).
By 1940 John Wayne was firmly established as a major motion picture star.
John Wayne had achieved stardom in motion pictures by 1941 and, by the end of the decade, was one of the cinema's top ten box office attractions.
During the latter half of the 1940s Wayne starred in what many film fans and critics regard as being among his finest work, notably the "cavalry trilogy" "(Fort Apache", "She Wore a Yellow Ribbon", and "Rio Grande)" for director John Ford, "3 Godfathers", also for Ford, and "Red River" for Howard Hawks.
Wayne also began producing some of his own films during this period.
The most discussed of Wayne's films during the following decade remains Ford's dark Western meditation on racism, "The Searchers".
Other popular Wayne films include the seafaring adventures "Reap the Wild Wind" and "Wake of the Red Witch" and influential war movies such as "Flying Tigers", "The Fighting Seabees", and "Sands of Iwo Jima", for which he was nominated for an Academy Award for Best Actor.
The 1950s would see Wayne continue as a major star although the artistic quality of his work varied greatly.
Wayne also continued his producing activities during this period as well, notably with the formation of his own production company, Batjac.
In 1960, Wayne appeared in his most personal production, portraying Davy Crockett in "The Alamo", which he also produced and directed.
During the 1960s and 1970s, John Wayne ranked as an American icon and one of the top box office attractions in the cinema.
Wayne's output of films consisted largely of Westerns but he also ventured into other genres as well, including several films dealing with the Second World War (notably "The Longest Day" and "In Harm's Way)".
Wayne made some of his most prominent films during this period, including John Ford's "The Man Who Shot Liberty Valance" (1962) with James Stewart.
Wayne's political views came under harsh attack from film critics with the release of "The Green Berets" (1968), which Wayne produced and directed as well as starred in.
The following year, however, he would be praised by critics for his performance in "True Grit", which would earn him an Academy Award for Best Actor.
John Wayne made his last picture, "The Shootist", in 1976, bringing an end to a remarkable career spanning more than 50 years, 169 feature length films, and various other television appearances or voice-overs. 
Doreen McKay is an American film actress.
She starred opposite John Wayne in the 1938 film "Pals of the Saddle" and the 1939 film "The Night Riders". 
The Three Mesquiteers is notable as the original entry in what became a 51-film series of Western "Three Mesquiteers" B-movies, eight of which starred John Wayne.
Filmed in 1936, the film stars Bob Livingston (in the role later played by Wayne), Ray "Crash" Corrigan, and Syd Saylor, and was directed by Ray Taylor. 
Acting career.
Carradine made his film debut in 1972 in "The Cowboys" with John Wayne.
He was also featured in a short-lived television series, of the same name, based on the movie.
He made an appearance as a killer in the Martin Scorsese film "Mean Streets" shooting to death the character played by his brother, David.
During this time he worked with David on some independent projects including a biker film called "You and Me" (1975) and an unreleased musical called "A Country Mile".
He also did camera work for David's cult classic Vietnam War inspired "Americana" which was not released until 1983.
In 1976, Carradine had the opportunity to demonstrate on screen what he considered to be his "first ambition", car racing, when he played Jim Cantrell in Paul Bartel's "Cannonball".
In the film Robert's character ironically wins the cross country road race, beating the favorite, Coy "Cannonball" Buckman, played by his brother, David.
In 1977, Robert became a snack for the vengeful killer whale in the "Jaws" imitation film "Orca".
In 1978, Robert landed a demanding role in Hal Ashby's Oscar winning Vietnam War drama, "Coming Home", which starred Jane Fonda and Jon Voight.
His performance caused some speculation that he might be the best actor in his family.
Robert was instrumental in securing his brothers David and Keith to perform with him in one of the most unusual casting arrangements in movie history.
Together the Carradines played the Younger brothers in "The Long Riders" (1980) along with three other sets of acting brothers: Stacy and James Keach, Dennis and Randy Quaid, and Christopher and Nicholas Guest.
Also in 1980, Carradine co-starred with Mark Hamill and Lee Marvin in Samuel Fuller's "The Big Red One" recounting Fuller's WW II experience.
His character, who was based on Fuller himself, narrated the film.
In 1983, he and Cherie Curie starred in the science fiction movie "Wavelength" in which he played a washed up rock star who helps extraterrestrials escape from a military base.
For the film he performed his own compositions including one named after his daughter, Ever.
Also in 1983, he starred in the music video for The Motels hit song "Suddenly Last Summer" as lead singer Martha Davis' love interestCarradine's biggest film success to date came in 1984 when he starred in "Revenge of the Nerds" as the lead nerd Lewis Skolnick.
To prepare for the comedy, Carradine spent time at The University of Arizona, where the movie was filmed, participating in rush week.
"No fraternity picked him, convincing Carradine that he was indeed right for the part of the nerd that nobody wanted to claim as their own."
Carradine reprised the role of Skolnick in three sequels, taking over as executive producer in the latter two. 
The book was adapted into a 1968 film of the same name starring John Wayne.
Production included extensive cooperation from the U.S. Army, which insisted that Moore not be involved with the film.
To please the Pentagon, Wayne bought Moore out for $35,000 and 5% of undefined profits of the film.
The movie version is noted for being one of the few films about Vietnam actually produced during the Vietnam War.
It is set in South Vietnam but was mostly filmed in and around Fort Benning.