"Almighty God--Our sons, pride of our nation, this day have set upon a mighty endeavor." It was with these words that President Franklin D. Roosevelt addressed the troops that were to mount the final assault on Nazi-dominated Europe on D-day, June 6, 1944. The Mighty Endeavor is a sweeping history of American action in the European theater in World War II, covering the entire scope of America's effort "to set free from Nazi tyranny a suffering humanity."From...