Cushman was a pathfinder in WWII; Pathfinders were parachuted behind Axis lines to prepare for the drop of paratroopers of the US army. It was arguably the most dangerous job for any American solder and Cushman did this in Sicily, central Italy, and then Normandy. He is a historian of considerable note and was actively engaged in freeing several Axis internment camps. He saw action on almost all European fronts in WWII. His books are the reflection of a man who was there did it and was part of it, not some library sitting academic historian who spends his time pontificating about the comments of events by journalists and other historians.