German army officers were astonished by the swiftness of the victory, the French collapse and the British escape. Later historians have hindsight and British writers can make much of Dunkirk but German writers take the view that although it was a big operational and perhaps strategic blunder, this could not be blamed on a German failure to have formed a concept of the war; Dunkirk might not have been decisive but was a fatal blow to German strategy. Melvin called the German victory a "stunning operational success"; the Germans had exploited Allied mistakes and recovered from theirs, despite the tensions in the German high command.[12]