@rokkinbobokkin in Star Wars, the creator of the Death Star said he thought the station would be used to mine dead planets, a tool for constructive use.
In real life, the creator of the rocket meant for them to be used to travel to other worlds, not for firing at one another. I believe he is famously quoted, "The rocket worked perfectly, only it landed on the wrong planet," most weapons that shouldn't be in the hands of regular people were created as tools for a purpose.