In Iraq I had a device called a Phraselator, an unwieldy specimen of 2004 military technology that resembled a cross between a fancy walkie-talkie and an early model PalmPilot. Like me, and all of the things in my life then, it was desert tan and armored to protect against rough treatment. The Phraselator allowed its operator to choose English phrases from a tiny, green-lit screen, then push a button and it would spit them out in Arabic to a listener. It was, characteristically enough for the military in western Iraq, issued to us in a rush of good intentions but came with no training for how to use it. I turned to it simply because I had it, and even so I only used it once.

We were tasked with capturing men who were planting improvised explosive devices in our swath of Anbar Province — or, if we couldn’t capture them, killing them. After another long day of finding nothing, I decided to use the cover of night to move on and hunt somewhere else the next day. When the sun rose on our new position, it revealed a single house 1,300 feet south of our location. Nestled among the low, rolling, desert hills, we had somehow missed it in the jade-speckled view of our night-vision goggles. It was small and simple; four dun-colored walls broken by small windows, a flat roof and a single door from which a man in an Iraqi police uniform emerged. He walked over to us.

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As the platoon commander, it was my job to handle any Iraqi police we encountered. Marines flanked my sides, loose but ready for the violence that could potentially accompany any encounter in Anbar. We stared at one another; I shook his hand and exhausted my Arabic with a single greeting. I smiled at him and he smiled back, each of us trying to communicate an absence of malice. Then I remembered the Phraselator. I ran to my Humvee and rummaged through my rucksack before triumphantly returning to the policeman with it, struggling to even turn it on. I fumbled through the menu, finding only greetings and incongruous conversational expressions, before desperately seizing upon the option of asking if the man needed medical care. A computerized voice delivered the question in Arabic. The policeman gave me a puzzled half-smile. Perhaps he couldn’t understand why an American Marine wearing 50 pounds of armor and weapons and holding a box that squawked out robotic Arabic would make him that particular offer. I tried a few more phrases while he stood awkwardly by, like a person at a party trapped in polite conversation with a drunk. Finally he nodded, turned around and walked back across the desert to his home. I left the exchange feeling as if I had faced an important test and failed.

The Phraselator turned spoken English into Arabic for American troops in Iraq.CreditJames Estrin/The New York Times

Fourteen years later, after more than two decades of military service, I still find myself stumbling when I try to talk to people about my experiences — as if I am once again standing before a stranger, punching keys on a machine I don’t understand, in a vain attempt to find a useful phrase that might bridge an ever-widening gap between me and him. Long before I went to war, I read Guy Sajer’s account of his service as a Frenchman conscripted to the German Army to fight the Russians during World War II. “A day came when I should have died, and after that nothing seemed very important,” he wrote in one passage. “So I have stayed as I am, without regret, separated from the normal human condition.” I feel that way sometimes. It’s as if the time I spent in that expanse of desert left me speaking a different language from my fellow Americans, a language that sometimes seems to have no translation.

“You weren’t actually involved in any real fighting over there, were you?” a childhood friend asked me on my return from Iraq. I felt as offended as if he’d walked up and slapped me. I felt invalidated by the very question. “Of course I was!” I shot back. “What do you think I’ve been doing for the past 10 years?!” I explained that we were tasked with the pursuit and capture of specific individuals, making our mission unrelentingly violent. We used plastic explosives to enter Iraqi homes in the dark hours, flowing through them like a flash flood, heralding our entry into each room with flash-bang grenades that felt like a punch in the head if you followed them too closely. We fought in the homes of our enemies, among their families. I told him what it was like to be in a firefight inside a house. How the blast of automatic weapons fire in a small room is so loud as to strip away conscious thought, leaving muscle memory born of rote repetition to determine who lives or dies. It was seven months of blood and fire and broken glass. He seemed discomfited by the exchange, and after a silence changed the subject. If a friend I’d grown up with, who knew me well, could not, or did not want to, understand what I was saying, how could I hope to explain it to anyone else?

On the way home from Iraq, we were herded into a tent in Kuwait and given forms that asked us to indicate the experiences we’d had by coloring in bubbles next to questions. Had I seen Americans wounded? Yes. Had I seen Americans killed? Yes. Had I seen Iraqis wounded? Yes. Had I seen Iraqis killed? Yes. Had I been shot at? Yes. Had I shot at anyone? Yes. We turned in the forms, then wandered the camp, constrained by huge sand berms, with little to do other than eat and ogle mannequins in skimpy lingerie being sold by Kuwaiti merchants. I was never asked about that form again. I still don’t know its purpose. It was the first of many occasions when someone asked me for my story but didn’t seem to know what to do with the answers.

Having spent the majority of the deployment cleaning ourselves under a single cold-water pipe, we took advantage of a nearby shower trailer reserved solely for Marines permanently assigned in Kuwait. Two such Marines entered as we basked in the steam from the hot showers. One of them demanded we leave. No one said a word, but the look in our eyes must have said something dire because the second Marine grabbed the first by the arm and simply said, “Back away, man, they’ve been up north,” and left us to ourselves. Even before we had left the region, even among our fellow Marines, we had already become disconnected. I wondered how we would explain to people back home the things we had done in their name. But I hold to the notion that there is value in the effort — value for me and, I hope, for the people who I talk to.

On our return to Camp Lejeune, N.C., we were freed to spend a night with our families. Unable to sleep, I woke my wife at 2 a.m. and made her watch “Napoleon Dynamite,” a movie that so divided my platoon I thought we would come to blows over its absurdities. I wanted her to see and understand something about the previous seven months of my life. I didn’t know how to tell her about a 2-year-old child toddling through window glass shattered by an explosive charge and leaving tiny, bloody footprints on the polished concrete floor of his home. Later that morning, more than a hundred Marines assembled in a final unit formation behind a large brick building immediately across the New River from a demolitions range. Before we were dismissed for the last time as a unified group, some Marines across the river detonated a substantial charge. We all visibly flinched, some of us dropping to the ground, all of us conditioned to dodge the shrapnel and fire that invariably accompanied loud blasts in Iraq. We looked around at one another and slowly stood back up, laughing at ourselves but sharing a level of understanding that has since been elusive.

Ironically, that common understanding is both the thing we most need from each other as veterans and the thing that keeps some of us from effectively reconnecting with civilians, a critical factor as we become civilians ourselves. Sajer’s notion of remaining separated from the human condition, though he claimed not to feel regret, is nothing less than self-imposed exile. Just as I felt when I stood before that Iraqi policeman, it is my responsibility to say something, to find some sort of connection. I just ask that you not get frustrated or awkward and turn away if the translation comes haltingly, or if the truth proves to be more than you wanted.