Imagine you an armed citizen walking down a busy street with a holstered gun under your jacket. A honking horn or perhaps someone's shouted greeting distracts your attention momentarily and you unintentionally bump another pedestrian. Annoyed, he responds in a menacing tone: "Hey, watch where you're going!" Naturally, you reach for your pistol and blow the troublemaker away, right there in broad daylight on a street full of shocked motorists and pedestrians. And you walk away, free from arrest because, obviously, that hostile stranger was threatening you, right?