Casualties of War is a 1989 war drama about the Vietnam War, starring Michael J. Fox and Sean Penn. It was directed by Brian De Palma, with a screenplay by David Rabe based on actual events that took place in 1966. An article written by Daniel Lang was the movie's primary source.

The theme of Casualties of War is how normal moral behavior is discarded during war times and shows it in the extreme when soldiers become savages who can dehumanize innocent by-standers, and also about personal responsibility for maintaining that morality in extreme conditions.

This film was Fox's second major dramatic role. A year earlier he had starred in the drama Bright Lights, Big City. John C. Reilly and John Leguizamo make their screen debuts in the film.

Tagline: Even in war... murder is murder.

The story is presented as a flashback of a Vietnam veteran.

A squad of American soldiers loses one of its members in a village in the Central Highlands which is believed to be an ally to the Viet Cong. In retaliation, the squad kidnaps a Vietnamese girl, Than Thi Oanh (Thuy Thu Le) to be their sexual slave, much to the objection of one soldier, Private First Class Max Eriksson (Michael J. Fox) who wants no part of it. His objections are quashed by the squad's psychopathic leader, Sergeant Tony Meserve (Sean Penn), who is antagonistic towards Eriksson because of his qualms of conscience. During a firefight, the troops viciously murder the girl to avoid being discovered by their superiors.

After the battle, they cover up the murder but Eriksson refuses to let the secret die. He jeopardizes both his life and military career (thanks in large part to indifferent superiors who prefer to bury the matter) to expose the crime. Eventually, there is an investigation and the four men who participated in the rape and murder are court martialed and receive long sentences. Sergeant Meserve received ten years of hard labor, Corporal Thomas E. Clarke(Don Harvey) received life in prison, Herbert Hatcher (John C. Reilly) received 15 years in prison and hard labor and Antonio Diaz (John Leguizamo) received 8 years of hard labor. Privates Hatcher and Diaz were later retried and acquitted on appeal after it was determined that their Fifth Amendment rights were violated and their confessions were ruled as inadmissable.

At the end of the movie, Max wakes up from the flashback he was having of the entire incident only to find himself on a bus just a few feet from a Vietnamese American student (also played by Thuy Thu Le) who resembles the kidnapped girl. She leaves the bus to go to school and forgets her scarf, with Max running after her to return it. They have a brief chat where she notices something is troubling him, and he explains that she reminds him of someone. They go their separate ways and the movie ends.