What is the theme tune for Vietnam lost films documentary?

The theme tune for the Vietnam lost films documentary is "The Ballad of the Green Berets". The song was originally recorded in 1965 and became a major hit for the band, The Ballad of the Green Berets. The song is about the United States Army Special Forces, who are commonly known as the "Green Berets". The song was used as the theme tune for the Vietnam lost films documentary, which is about the thousands of films and videos that were lost or destroyed during the Vietnam War. The documentary focuses on the efforts that have been made to recover these lost films, and the importance of these films in preserving the history of the Vietnam War.