Daniel, who’s under FBI investigation, is one of three former military operatives featured in the documentary “National Bird.” (Torsten Lapp/FilmRise)

Making her feature debut as a documentary director, investigative journalist Sonia Kennebeck focuses on three former operatives in the U.S. military’s controversial drone warfare program: Air Force veterans Heather Linebaugh and Lisa Ling, and a signals intelligence analyst identified only as Daniel. (He’s under investigation by the FBI for espionage.) Their stories of witnessing collateral civilian deaths are disturbing, but less so than watching a clip of an actual Predator attack, and then listening to some of the Afghan survivors.

“National Bird” puts forward an artful, profoundly unsettling argument against these inherently sloppy operations. Kennebeck may be a newcomer to feature filmmaking, but her grasp of the material is accomplished. That’s why the film was executive-produced by Wim Wenders and Errol Morris, two pros who recognize not only talent, but also incendiary material when they see it.

Unrated. At AMC Hoffman Center 22. Contains obscenity and images of drone warfare and the resulting injuries. 92 minutes.