«The Invisible Enemy» by Arnold Castle

The Invisible Enemy by Arnold Castle - At fifteen he was sent to war to fight an enemy he couldn't understand. But more puzzling was the victory to be won—after he met defeat!
It was the day.
The automobile with its three passengers moved slowly along the quiet morning street. There was no need for hurry.
The boy's father was soberly recalling his own war experiences, wondering how similar Tom's would be. The mother was remembering vividly fragments of films, of facsimile reports, of forgotten conversations, envisioning her son cringing pathetically in a shallow foxhole as the penultimate weapon burst into grisly glory in the dark dawn sky. Tom's own thoughts were tense, but he managed to conceal his nervousness from his parents.
"We're here, son," his father announced calmly, pulling the car up to the curb.
"Dear, can't we drive around the block just once?" his mother asked, her voice almost a whisper.
"We're early."
"No, mom," Tom said crisply. He opened the door and stepped out onto the sidewalk.
"Want us to go in, son?"
"No thanks, Dad."
"But we want to, Tom," his mother said. "Of course, we'll go in!"
"There's no need for you to. I'm already registered," he told her. He reached out to grip his father's hand.
"Tom!" his mother protested.
"Don't worry about me." He kissed her hurriedly, and was relieved when his father drove away without waiting for him to start up the steps. He knew that they would worry, and he turned abruptly, forcing his attention away.
The day was bright and a chill breeze swept in from the Pacific. Atop a distant hill eucalyptus glimmered in the white sunlight. Inscribed over the portal of the modest building which he now faced were the words:
DEPARTMENT OF PEACE "THAT THE AGE OF VIOLENCE MAY FOREVER REMAIN HISTORY"