SciFi story about a planet where wars are eradicated

[Nikolai]

This SciFi story is about space travelers visiting a planet where wars are extinct, no armies, no murders. They are very excited and decided to come back there soon. But when they return there in a while, the planet is destroyed by another aggressive space race.

I've heard about this story maybe 20 years ago. And I believe it can be older.

[Lobstergirl, au gratin]

Was the story in an anthology? If so, was it an anthology with multiple authors, or just one? Or was it in a magazine? Etc.

[Nikolai]

Lobstergirl wrote: "Was the story in an anthology? If so, was it an anthology with multiple authors, or just one? Or was it in a magazine? Etc."
My guess, it could be an "Anthology of Western SciFi writers" or something.