What began as a mentor-mentee relationship has bloomed into a professional partnership that finds Michael Kahn and Sarah Broshar sharing credit as the editors of Steven Spielberg’s “The Post.”

Broshar met Kahn, who has been working with Spielberg for four decades, when she was an assistant editor on the director’s “The Adventures of Tintin” (2011). She went on to work with Kahn and Spielberg on “War Horse,” “Lincoln” and “Bridge of Spies” before earning a full editor’s credit on “The Post.”

“I feel very, very lucky to have Michael as my mentor,” she says. “It’s been a really rewarding process to sit with Michael and Steven and learn the craft.”

The duo were just nominated for an ACE Eddie Award by American Cinema Editors.

At the time that Kahn and Broshar cut “The Post,” which tells the 1971-set story of how The Washington Post came to publish the Pentagon Papers, Spielberg was still shooting the film. They worked in an editing trailer that followed the production everywhere it went. Spielberg was in and out of the trailer each day, running dailies with them.

“It’s a process that we’ve had for many years,” Kahn explains. “I like him to select the takes he’d like to use. That saves a lot of time for everybody.”

That said, there’s a back and forth as the assembly progresses. “Michael and Steven have a long-standing joke where Steven will ask for a set of changes, and Michael will say, ‘OK, great. I’ll see you in a week,’ then Steven will be back in an hour to see the take,” Broshar says. “He knows it will be done.”

Some of Kahn’s and Broshar’s best work in the film shows the power of restraint. For example, in a scene that depicts a breakfast meeting between Post publisher Katharine Graham, played by Meryl Streep, and managing editor Ben Bradlee (Tom Hanks), the editors stay on a two-shot of their conversation for quite a bit of time. “We just cut the slates off. A cut at the head and a cut at the tail, and we’re great editors,” Kahn says with a laugh.

More seriously, Kahn points out that Bradlee is talking fast in the scene, and Graham is doing a lot of listening, so to go back and forth “would have been very ‘cutty.’” Holding on that two-shot “sort of makes you feel like you’re sitting at the table with them, and it’s your eyes choosing who to look at,” Broshar adds.

The editors also deftly employ montages throughout the film, including a tense, informative sequence near the start that intercuts footage of Matthew Rhys as Rand Corp. analyst Daniel Ellsberg, making photocopies of the Pentagon Papers, with archival clips of past presidents speaking about the role of the United States in Southeast Asia.

“Sarah did a lot of that. She put it together and I looked at it, and we both worked on it. When it got to Steven, it was about what it should be,” praises Kahn, who says the job ultimately comes down to instinct.

“In editing, there’s no right or wrong,” he muses. “It’s just ‘Is it as good as it can be?’ That’s the question.”