If only for a day.... I don't know how long this will last or how Amazon.ca (yes, Canada's Amazon, not the US's) counts stuff. The book is also 4th on 20th Century Canadian history right now, but the book contains no such thing. Military stuff? Absolutely.
Anyhow I am going to take this and run with it, as I have never been at the top of any best-seller list, even one might just require five people to buy the book on the same day.