Best way to explain castle doctrine to my wife?

So my wife is watch the Foster's when an old man threatened anyone who comes onto his property to destroy his Xmas decorations will have to answer to him and a baseball bat. I made a comment about how he'd be in jail when she said "so you wouldn't shoot someone stealing but you'd shoot someone who broke in?" I said yeah and explained castle doctrine but she still didn't get how it was worse. Any advice? via /r/CCW http://ift.tt/2bZqRsI