Another similar SF story is the one by Larry Niven where a human ship meets the Kzinti for the first time. Earth has been at peace for so long that the human crew literally have no concept of violence or war at all, except for an abstract historical concept. The warlike Kzinti pick all this up from comms and decide that since the Earth ship's technology is interesting, rather than blow it up, they'll just kill off the crew of "ridiculous weaklings" with an induction beam that heats it up and then take it home with them.
The human crew are utterly mystified as to why their ship is heating up and why the intelligent aliens (who MUST of course, be peaceful) don't want to talk to them, until one of them, a history buff, puts two and two together and realises the unthinkable truth. The humans turn their unarmed ship around, as if to move away..... then kick in their star drive at point blank range, cutting the Kzinti vessel in half and killing everyone aboard. They then head home in the blackest of depressions with the awful news that humanity is going to have to learn the killing game all over again.....
Edit - the story is called "The Warriors".