Dwight Eisenhower was no writer, but if you want to get a feel for what excruciating planning went into D-Day, read his "Crusade In Europe." They worked on the invasion for years, both the military side evaluating the beach, the tides, the weather patterns, but equally the international politics, the politics between military leaders of various nations, and so on. Even Patton, in temporary disgrace for slapping a shell-shocked GI, was used as a decoy to mislead the Nazis as to where the landing would be made. The book is endless detail, and can get pretty dry, but at least you know that despite the grim chances for GI's making the landing, thousands of people had spent years making it the best bet it could be. I guess a few true warriors were only looking for some Nazis to shoot, whereas everyone else was casting their fate to the winds and moving forward. Homework payed. Even when he was a former President, Eisenhower wept when he spoke of the sacrifices.