The Foxholes of Mars by Fritz Leiber

Ever inward from the jagged horizon the machines of death crept, edged, scurried, rocketed, and tunneled towards him. It seemed as if all this purple-sunned creation had conspired to isolate, to smash him. To the west—for all planets share a west, if nothing else—the nuclear bombs bloomed, meaningless giant fungi. Invisibly overhead the spaceships roared, distant as gods, yet shaking the yellow sky. Even the soil was treacherous, nauseated by artificial earthquakes—nobody’s mother, least of all an Earthman’s.

“Why don’t you cheer up?” the others had said to him. “It’s a mad planet.” But he would not cheer up, for he knew what they said was literally true. Soon they would fall back and the enemy would retake the mangled thing they called an objective. Was it the sixth time? The seventh? And did the soldiers on the other side have six legs, or eight? The enemy were pretty haphazard as to what troops they used in this sector.

Worse was the noise. Meaningless, mechanical screeches tore at his skull, until thoughts rattled around in it like dry seeds in a dry pod. He started to lift his hands to his ears, then checked the gesture, convulsed with soundless laughter and tearless weeping, bitter memories and searing hatred. Once there had been a galactic society—a galactic empire—and he had played an unnoticed part on one of its nice quiet planets … but now? Galactic empire? Galactic horse-dung! Perhaps he had always hated his fellow men as much as he did now. But in the prewar days his hatred had been closely bound and meticulously repressed.