Harry Turtledove has definitely found the right balance (no pun intended) between Alternate history, Sci-fi, and Military Techno-thrillers. This book (the third in a four part series) Keeps the reader constantly wondering "what's next?". In fact the unpredictability of main characters fates is what makes this story so interesting. Some hard core Sci-fi fans may find the plot and alien gee-whiz gizmos tame compared to other outer space invader novels, but for those who like Tom Clancy and Larry Bond type Military Techno thrillers, this book has action aplenty, and enough different story lines to keep readers from becoming bored. The aliens employ weaponry which seems to be based loosely on today's military technology, making it easier for average people to imagine how the stuff works. The author has also obviously done his homework on the geographical areas mentioned and the life and times of people who lived during the World War II era. The detailed way people, places, and events are described leaves little to the imagination, putting the reader right there with the characters. Overall this reviewer found this to be the best of the three novels so far, although it doesn't really stand on it's own, so the first two books in the series need to be read in order first to really appreciate it. This reader eagerly anticipates the release of the last of this four part series "Worldwar; Striking the Balance". The only negative comments about this series so far is the time between releases as another reader has already mentioned. It's probably a marketing ploy to sell as many hardbacks as possible, then bring out the new book about the same time the last one comes out in paperback. Very clever