If I'm reading your story it's only because you've given me a reason to go to page two and I want to know how the story comes out. If you stop your story to put a creep on Obama or Bush or Clinton, YOU HAVE STOPPED YOUR STORY! It knocks me right out of your tale.
I don't care about your politics, digestive system, home life, or views on global warming. I want the story. If you want to badmouth a politico, go to the neighborhood bar and regale the other pundits there with your views. When you get to your keyboard, allow only the storyteller to tickle the keys.