What happens if your daughter comes home early from a sleep over? You definitely have a plan, you would shoot and kill her. What happens if your son is feeling depressed? You definitely have a plan, you allow him to shoot himself. These are far greater risks than a thug breaking into your house, not caring about stealing things, only wanting to hurt people.
In life you play the odds. I look at the odds of dying in a household with a gun, and see they are much higher, and play the odds based on that.