One Book to Explain Yourself: What Would It Be?

Here’s a question I’ve been asking people and they were very interested in the answer – which I do not have. We (liberal and conservative relatives) were discussing the splits in the country and I was saying that we’d do better if we learned the basics of the other side’s arguments as presented in the blogs and I thought it was really only ten or twenty books.

So – What are the books powering the blogs in America – the main book, the key book?