A comprehensive notion of what turned American soldiers against the Vietnam war has taken some time to reach us, and this affecting documentary by David Zieger collects many potent testimonies evoking veterans’ activism from 1966 to ’71 (a period when the Pentagon recorded 503,926 “incidents of desertion”). Zieger interviews about a dozen vets from all branches of the service and finds that the war’s injustice, particularly the systematic killing of innocent civilians, was a galvanizing factor. (John Kerry was excluded as a possible distraction, but Jane Fonda speaks eloquently about her “Fuck the Army” tour of U.S. military bases with Donald Sutherland.) I expected to emerge depressed by how long these stories have gone untold, but the speakers’ courage and humanity are a shot in the arm. 84 min. Landmark’s Century Centre.