directed by Frank Capra, music by Dimitri Tiomkin, narrated by Walter Huston, Questar Video, 3 hours 53 mins., $59.95 . CODE: QSV-1

This film, made for the War Department in 1942, doesn’t teach history so much as give an unsettling sense of the terror of the time when it was made. Imagine you are a raw recruit sitting in the dark on the eve of service. The government will make its case against the enemy during these few hours. Why We Fight may seem bombastic and crude fifty years later, but it also very effectively fulfills the assignment given to Frank Capra, whose public-spirited Hollywood features then included Meet John Doe and Mr. Smith Goes to Washington . “Why are we Americans on the march?” the first part, “Prelude to War,” begins. “Could it be Pearl Harbor?” (explosion) “Britain?” (droning planes and bombs) “Norway?” (explosion) “Poland?” (explosion). Capra shows two globes, one free and one enslaved. Books go spinning into German bonfires; a Japanese dagger sinks into Manchuria. The second part, “Divide and Conquer,” while no less bellicose, uses more newsreel footage and fewer corny props, offering a brief refresher course in Hitler’s early tactics. Our Russian allies look positively heroic, and the film’s final segment, “War Comes to America,” brings the message thumping home. Capra’s film generates both heat and light in sketching out the battle against the “three gangsters.”