American history is exciting, first of all.  We are really the only modern nation whose entire career in our history is available to us; that is, we go over the first papers, the settlement of Jamestown, all the way down to the present, and the documents are there.  There are no mysteries about it.  If you were writing about the history of England or Sweden or so on, you’d have to go back in the depth of time and still wouldn’t know how the things began.  So, in America, you have a kind of case study of the development of a nation and how it grew and why it grew and why it grew in this particular way, and this has always had a special fascination for me.  With the Civil War, it is, in particular, the fascination of two roads.  One might have led to an independent Confederacy, two nations under this continent, what would have happened since that time, and so it encourages you to imagine things that were different, and the other was the road that was taken.  So one puzzles over these aspects and tries to figure out what can I do with this, what can I make out of it.