Here’s the transcript of a recent interview I did with Rebecca Frankel, author of War Dogs: Tales of Canine Heroism, History, and Love.

Tell us about the piece that you wrote for Foreign Policy that inspired this book. What moved you to expand on “Rebecca’s War Dog of the Week” and bring it to the larger public?

In early January of 2010, I came across a photo of a Marine battalion operating out of Helmand Province, Afghanistan. I did a lot of photo editing for the magazine—and still do—and during that time, U.S. troops were still heavily engaged in fighting on the ground. But this photo surprised me—not for its grit or gore, but because the Marines in the image looked happy, content, and very much at home. They were with two bomb-sniffing dogs.

I shared the photo with longtime journalist and former war correspondent Tom Ricks (who is also a great lover of dogs), and he suggested we post a war dog photo every Friday. After digging into the topic, I discovered that it was not only rich with great photos, but also with history, stories, and remarkable examples of how dogs can be tremendous assets in war. So, that’s where Rebecca’s War Dog of the Week came from and how I started working on a military canine beat.

About a year and half later, in the wake of the Osama bin Laden mission, came the news that a dog had been attached to the elite force sent in to take out the world’s most wanted man. So I pulled together a collection of some of the best Military Working Dog (MWD) images I could find and wrote up captions to explain why they’d have brought an MWD on this mission. The photo essay, War Dog, went viral.

And so I really was very fortunate—though I’d had the idea for the book, the photo essay brought the opportunity to write it directly to me.