This is a sci-fi story by legendary American writer Frederic Brown. Do yourself a favour, go buy this AMAZING collection of very short stories of his. Or find some for free here.
Yeah I know, I’ve got no Amazon affiliation :/
He was wet and muddy and hungry and cold and he was fifty thousand light years from home.
A strange blue sun gave light, and gravity, twice what he was used to, made every movement difficult. But in tens of thousands of years this part of war hadn’t changed. The flyboys were fine with their sleek spaceships and their fancy weapons. When the chips are down, though, it was still the foot soldier, the infantry, that had to take the ground and hold it, foot by bloody foot. Like this damned planet of a star he’s never heard of until they’d landed him there. And now it was sacred ground because the aliens were there too.
The aliens, the only other intelligent race in the Galaxy…cruel, hideous and repulsive monsters. Contact had been made with them near the centre of the Galaxy, after the slow, difficult colonization of a dozen thousand planets; and it had been war at sight; they’d shot without even trying to negotiate, or to make peace. Now, planet by bitter planet, it was being fought out. He was wet and muddy and hungry and cold, and the day was raw with a high wind that hurt his eyes. But the aliens were trying to infiltrate and every sentry post was vital. He stayed alert, gun ready. Fifty thousand light-years from home, fighting on a strange world and wondering if he’d ever live to see home again.
And then he saw one of them crawling toward him. He drew a bead and fired. The alien made that strange horrible sound they all make, then lay still. He shuddered at the sound and sight of the alien lying there. One ought to be able to get used to them after a while, but he’d never been able to. Such repulsive creatures they were, with only two arms and two legs, ghastly white skins and no scales.