As a rule, I am very skeptical of tying books to anniversaries. I don't think readers care. I also feel that it just about guarantees that somebody else will be writing a book on the same subject, but being a former journalist, I'm always interested in, like, why write about something today? Why do it now?

One question that often comes up is why, in this age of blogs and tweets and instant digital communication of all kinds, it still takes so long to publish a book.

I have found from experience that it is often interesting and useful to start from the edges and work inward - another flaw of mine. I seldom approach things directly. I would have made a great moth.

I knew from an online search that the Wisconsin State Historical Society, on the vast University of Wisconsin campus, held the papers of Sigrid Schultz, a spunky correspondent for the 'Chicago Tribune' who became one of Martha Dodd's friends in Berlin.

It was David McCullough's 'The Johnstown Flood' that lit my imagination as to how I might one day go about writing book-length nonfiction, though my favorite of his books is 'Mornings on Horseback,' about the young Teddy Roosevelt.