There are other published books that shed light on the role of Russia before, during and after the Second World War. In the case of this book, after the first (bolded) line in the description, it descends into the lows of hyperbole which no book like this should have. That said, I mention it since this change of focus is helping to add perspective.
Scheduled for 20 April 2021.
https://www.amazon.com/Stalins-War-N.../dp/1541672798
usual disclaimer,
Ed