"If one of those poor people on the island had a gun, the killer would be toast. He'd have got off a few rounds and then sayonara. Is this not the best case for guns I've seen?"
No it isn't.
If it were, the US would be the safest place on earth. Look how many mass shootings there have been over there, and count the number of times Joe Public has managed to take down the perpetrator with a firearm. From my recollection, the answer is 'none'.
