According to Merriam-Webster Online, “blowback” refers to “unintended consequences of a covert operation that are suffered by the civilian population of the aggressor.”

A powerful new documentary, “Dirty Wars,” is scary proof that blowback is here again.

The filmmakers, including director Richard Rowley and reporter Jeremy Scahill, found themselves drawn into the story of a brutal, secret American government operation carried out with drones. Rowley and Scahill got to know an Afghan family that had been partly wiped out.

The film found its narrative shape when a co-writer, David Riker, urged Scahill to provide a focus by emphasizing Scahill’s investigative role on-camera. While this approach, combined with Riker’s shadowy photography, has drawn complaints about hokeyness, it’s consistently effective.

“You get some very fascinating people at the talk-backs, the discussions,” said Scahill, when he brought the film to the Seattle International Film Festival in May. Hesitant at first about “playing” himself, he now thinks this approach helped to provide a necessary structure and a nonpartisan context.

“I didn’t want to be a character in the film,” he said. “I was always going to be in the film, but not as me.” The role grew from “tour guide” to detective.

By emphasizing the human cost of the operation, Scahill and Rowling turn “blowback” into much more than an abstract military-political term.

John Hartl: johnhartl@yahoo.com