Suppose someone is trying to kill you or your loved ones. Do you really not see how a gun could be beneficial? Do you really not see how killing someone could be the right thing to do?
On the front page is a story about someone recovering a camera from a thief. One comment says that confronting the thief could be dangerous, since they might have a gun ( https://news.ycombinator.com/item?id=5505464 ). Here in Ireland if some low level criminal stole my camera, they wouldn't have a gun when I meeting them in a café.