"This book is about restraint, something I am not known to practice very frequently. But I have had to practice it in writing this book, and I've learned patience in the process because I think restraint is incredibly important for politics, and especially for international relations. I continued to slog away at this book precisely because I received so many comments, notes of encouragement, and critically important pieces of advice from friends and colleagues who also shared a sense that there needs to be a book like this one on restraint. It has taken me well over the course of five years to research, present, write, revise, and re-revise the content that went into it. In my more melodramatic moments I've referred to this book as my 'white whale'"--