There to capture them is Ishmael’s unit, one of three history teams deployed to Afghanistan. Another four are in Iraq. All are descendants of the teams that roamed the European and Pacific theaters during World War II, collecting soldiers’ stories. Among the lessons from that trove was the combat historian S. L. A. Marshall’s finding—hugely influential, even though questioned in recent years as slightly exaggerated—that many men didn’t fire their weapons in combat, and were reluctant to kill, even when in mortal danger.

Soldier-historians interviewed troops and collected documents during the Vietnam and Gulf wars, and their appetites have since become voracious. Over the past decade, the U.S. Army Center of Military History has gathered 30 terabytes of interviews, briefings, photos, and maps—roughly equal, by some estimates, to the printed contents of the Library of Congress. Ishmael’s team, at Bagram Airfield, just outside Kabul, collected more than two terabytes during its deployment, which ended in January. “Hopefully by doing this we won’t be unprepared again,” says the 135th’s commander, Major Donald Loethen. At home, he works in marketing at Michelin, but he studied history (the European Reformation) at Lincoln University in Jefferson City, Missouri. “People will know what happened when they’re planning for the next Afghanistan,” he says. “And there will be a next Afghanistan.”

To do his job, Ishmael carries a 9-mm pistol and an M-4 rifle, a digital voice recorder, a camera, and a notebook, and travels to small forward operating bases, where in between interviews, he patrols with soldiers. “You go outside that wire, there is no control. None. There’s a bomb out there with ‘To whom it may concern’ written on it,” he says. “That’s why, as an historian, I need to go out with the guys, to gain that perspective, to understand what’s important.” For big operations, Ishmael and his team might speak with several dozen soldiers; Ishmael reckons he interviewed about 100 during his deployment with the 135th. They gather initial plans and maps, communications during the fight, and after-action reviews that analyze intent versus outcome. “If it didn’t turn out the way it was supposed to, why? That’s the question,” Ishmael tells me.

Ishmael, who works as a financial adviser in Maryland Heights, Missouri, but dreams of teaching history, knows that the terabytes of documents and interviews will likely sit in a digital warehouse for years. Though Army historians have used the materials to write two books on Iraq—one on several small battles and the other on the 2007 troop surge—the Center of Military History is two or three years behind in reviewing the teams’ data, and doesn’t yet have a robust search engine; moreover, civilian historians and journalists can’t access the materials, because they’re still classified. But the reports will eventually be made public, and someone, someday, will use his work, Ishmael says. “All this joy I’ve gotten out of the books I’ve read—I get to provide future historians with the meat of their books. I’m providing my kids and my children’s children with the context of what we’ve done,” he says. “We’ve been here for 10 years. That’s a big part of America.” As he points out to me, his 11-year-old son has never known the United States not being at war.