A war decided by mechanism, mass production, competitive design produces a different type of war. This is not an analysis of those differences, but a useful resurvey of the course of war from the proving ground of the Spanish Civil War, the -- remilitarisation of the Rhineland and the Austrian Anschluss down to the capitulation of Roumania and the reoccupation of France. The author recognizes the impossibility of weighing cause and effect, but his telescoping of the progress of war clarifies such in viewing events at some distance, -- the campaign of aggression, the effect of Pearl Harbor on the overall picture, the Battle of the Atlantic, the Russian counter-offensive, victory in North Africa. Then -- with Hitler's handicap balanced out, the change on three fronts, -- the Russian siege broken, the Mediterranean opened, the battle against the submarines won. The air war against Europe then at full speed ahead -- but a slowed up supply problem and the Italian stalemate postponed for a month the Normandy invasion...Useful reference book -- a reminder of things known but soon blurred.