Released in 1965, "Why Vietnam?" was produced by the U.S. Department of Defense to aid public acceptance of the Vietnam War and to indoctrinate Vietnam-bound draftees. Structured in the rhetorical tradition of the "Why We Fight" films, it draws historical parallels to World War II, depicts U.S. military activity in Vietnam, and presents official interpretations of the conflict’s origins. Later criticism by historians highlighted the film’s selective use of evidence and its distortion of key historical facts, revelations that were further underscored by disclosures in the Pentagon Papers.
| Actor | Role |
|---|---|
 Adolf HitlerSelf (archive footage) | Self (archive footage) |
 Lyndon B. JohnsonSelf (as Lyndon Johnson) | Self (as Lyndon Johnson) |
 Robert McNamaraSelf | Self |
| DDean RuskSelf | Self |
 James ArnessNarrator | Narrator |