I FIRST BECAME interested in international politics almost half a century ago, during my freshman year in college at Berkeley in 1963. From the start I knew that this was the field I wanted to go into, and in fact I have spent practically my whole life working in this area; my particular focus has been the history of great power politics in the twentieth century One of my main goals at this point in my life is to pass on what I have learned over the years about how historical work in this area can be done, especially to people just starting out in this field. To that end I recently published a book on historical method called The Craft of International History. But although I tried there to be as concrete as I could, it seemed to me that I could do more to show how in practice an historian interested in this area of scholarship could proceed.
If I had to sum up in a single sentence what I have learned over the years about how historical work on international politics should be done, it would be this: the key to doing meaningful work in this area is to find some way to get conceptual and empirical issues to link up with each other. I don't think it makes sense to approach the core issues that this field is concerned with—above all, the great problem of war and peace—on a purely abstract level. That sort of theorizing, to my mind, cannot in itself take you very far. On the other hand, a purely empirical approach is also fairly sterile. There is not much point to simply accumulating a lot of facts. You need some way to figure out what they mean, and to do that you need to bring a kind of conceptual framework to bear—if only to generate the questions the empirical evidence can help answer. But general points of this sort are in themselves rather anemic. Their meaning sinks in only when you see how historical work that takes those principles as its point of departure can actually be done.
The basic aim of this book is therefore to show through example how to go about doing that kind of work. Only one of the articles included here (chapter 2) is directly concerned with issues of method, but all the articles, in one way or another, show how that fundamental approach works in practice. The first chapter, for example, on the question of realism, shows how the sort of understanding that takes shape in your mind as you grapple with historical problems can be brought to bear on core theoretical issues—on fundamental questions about what makes for war or for a stable international system. It was written as a kind of reaction to what I had found in the international relations literature. It