First, the motivation for putting the new preface on the book had to be purely marketing. The preface had a much different tone to it than the text of the book. I read the first few pages of the preface and almost put the book down because in my opinion it took a much more critical, preachy style to it. The preface would have been much better as an Epilogue. In general, I thought that the book was much more balanced than the preface.
Second, the author did not establish the basis for the sub-title:"...Roots of Middle East Terror." In fact, I'd almost argue that the title itself is really not even reflective of the substance of the book.
More than half of the book is devoted to the details of the career of Mohammad Mossadegh who walked a tight-rope politically to nationalize Anglo-Iranian Oil. It's definitely a story worth telling and reading, and the author does a good job with it. So I would recommend this book to anyone intersted in US-Iranian politics. To understand how we deal with Iran now, and how they dealt with the US in 1979, you need to understand what happened in the early 1950's between Iran, Great Britain, and the US.