More than 65 years after it was suppressed by the Army, a powerful and controversial John Huston documentary about soldiers suffering from the psychological wounds of war has been restored by the National Archives and debuts Thursday on the Web.

“Let There Be Light” portrays GIs just back from the battlefields of Europe and the Pacific — trembling, stuttering, hollow-eyed and crying. Using a noir style, Huston filmed dozens of soldiers in unscripted scenes from their arrival at an Army psychiatric hospital on Long Island through weeks of often successful treatment, culminating in their release to go home.

The restoration “reveals the film’s full force,” said Scott Simmon, a film historian and English department chairman at the University of California, Davis....