Trees move at night. My father taught me this when I was a single-digit boy and he was eleven years home from the war in Korea. “At night over there, the trees never stayed still,” he told me. “If you looked away and then looked back, the trees were never where they had been before. It looked like the North Koreans were hiding behind the trees to sneak up and kill us.”

We were walking from our farmhouse to a barn seventy yards away. Cows slept inside on straw bedding during winter. They started calving in March, but the possibility of premature births meant we checked them nightly starting soon after each new year’s. Illumination was by flashlight, always, and moonlight sometimes. Shadows danced everywhere.

“The trees at the front in Korea looked like Iowa trees during the daytime,” my father would say as we walked in the dark. He pointed his flashlight beam toward invisible evergreens my mother’s grandparents had planted as a windbreak west of our farmstead. “I wanted them to look like Iowa trees at night, too, but they never did.”

The accumulated walks meant nothing about night frightened me. I could follow the fence lines of our pastures, sketch every corner of the barn, knew the cows — which ones kicked, which ones were gentle and allowed me to run my hands across their backs and scratch them. I could see everything even in the dimmest light, or none.

Decades later, as a journalist, I visited Seoul and the so-called peace village at Panmunjom and what passed for the South Korean countryside. I stepped outside my hotel after dark to imagine the place when my father had appeared in arms. The lights of prosperity, freedom were too bright. My experiment failed.

My father, married not quite a year and sharecropping a piece of Iowa black dirt owned by a wealthier man, had been drafted into the Army in 1951 and sent to a land whose winters were even colder than Iowa’s. He had a piece of luck: When his Pusan-bound troopship of infantry replacements stopped to refuel in Japan, Army recordkeepers, who’d spied his high scores on a stateside test of mechanical aptitude, pulled him out.

The military’s notice was inspired. My father had quit high school to help his own father on the farm. He learned how engines worked, how flywheels could power harvesters. War machinery, with its tracked vehicles and moving parts, was familiar to him. So he would serve not in the infantry but in the artillery, King of Battle, a few hundred yards back from the front.

In Korea, my father discovered the many ways soldiers his age could be killed or wounded. Some deaths came from carelessness, error or metal fatigue: accidental discharge of a rifle or pistol, say, or an overturned vehicle, a faulty Jesus nut on a helicopter. Other losses were inflicted by the enemy.

My father had been caught outside during intense shelling. He ran left to safety in a sandbagged bunker. His friend Leonard, from Michigan, ran in the opposite direction, intersecting with shrapnel that shredded his abdomen. “Leonard got hurt real bad,” my father told me during one of our January walks. “The Army sent him home, but his insides never worked right after he got hit.”

My father spoke of Leonard as Vietnam seeped into the news. That war ended before I was old enough to be drafted, although half a dozen boys from farms near to ours spent their late teen years there. “I don’t know how they can fight a war when there’s no front line,” my father said to me when we watched Walter Cronkite on the evening news.

Leonard and my father telephoned each New Year’s Eve. On one such evening, the telephone rang. My mother answered, said hello, listened a moment, then passed the phone to my father. “Hello Leonard,” my father said. “Is it cold there in Michigan?” Then more pointedly: “I bet it isn’t as cold as it was in Korea. Remember, Leonard?”

My father’s back was to me as he spoke to his friend from sixty years before. I heard him smile. Outside, the winter wind whipped nearby tree branches. The trunks held steady, unmoving, in the darkness.

Mr. Svoboda, a former Africa Editor of the Economist magazine, is an associate professor at the City University of New York Graduate School of Journalism.