“Korengal” director Sebastian Junger finds war reporting “pretty compelling.” (Tim Hetherington)

There are questions you don’t ask combat veterans. You don’t ask them how many guys they killed. You don’t ask them what it feels like to kill someone. You don’t ask them “what was it like over there?”

Because if you’re not a combat veteran yourself, you’re not going to understand it. Unless you’re Sebastian Junger.

The director of 2010’s Oscar-nominated “Restrepo” and “Korengal,” opening Friday, along with his “Restrepo” co-director Tim Hetherington, spent 15 months, off and on, in 2007 and 2008 with a platoon of soldiers serving in one of Afghanistan’s deadliest valleys. Junger and Hetherington did everything but “shoot back and pull guard duty,” Junger says, and he could ask the questions most civilians can’t.

“Tim and I knew the guys. Most of the guys who were killed out there we knew personally and were upset about,” Junger says. “The soldiers didn’t have to explain combat to me. I was by their side through a lot of it.”

Prior to making “Restrepo” and “Korengal” — which uses footage shot for “Restrepo” but puts more emphasis on contextualizing and explaining combat through interviews conducted with the soldiers once they returned to their base in Italy — Junger and Hetherington were longtime war reporters for various outlets.

“I’m a journalist,” Junger says. “My job is to cover important stories.” When it’s pointed out that there are plenty of journalists who cover important stories that don’t involve great personal risk, he says, “I felt the dangers were pretty small [in Afghanistan]. One hundred and fifty men in that platoon, with six killed in 15 months? Those odds are OK.” Then he pauses. Though Hetherington was involved in the filming for “Korengal,” he’s not a co-director this time around — he was killed in a mortar attack while reporting from Libya in 2011.

“I got out, anyway,” Junger continues. “After Tim got killed I stopped war reporting pretty instantly after I got the news. But it’s pretty compelling. In some ways, there’s nothing I’d rather be doing.”

That echoes the sentiment of the soldiers in “Korengal,” many of whom talk about how they can’t wait to go back into combat. It’s clear Junger feels that longing.

“I mean, look, I used to smoke,” he says. “I miss smoking; it’s such a pleasure. You have these moments of ‘oh, I wish I had a cigarette,’ of really fond memories of that time in your life. But you’re glad you’re not back there doing it.” And, for a moment, it almost seems he’s convinced himself he’s telling the truth.

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