Although Hitler never referred directly to the lightning thrust made in 1940 through the Ardennes as being in any sense a prototype for the operation in the same area four and a half years later, there is indication of a more than casual connection between the two campaigns in Hitler's own thinking. For example, during the 16 September expose he set the attainment of "another Dunkirk" as his goal. Then, as detailed planning began, Hitler turned again and again to make operational proposals which had more than chance similarity to those he had made before the 1940 offensive. When, in September 1939, Hitler had announced his intention to attack in the west, the top-ranking officers of the German armed forces had to a man shown their disfavor for this daring concept. Despite this opposition Hitler had gone ahead and personally selected the general area for the initial penetration, although perhaps with considerable stimulation from Generalfeldmarschall Fritz Erich von Manstein. The lightning campaign through the Netherlands, Belgium, and France had been the first great victory won by Hitler's intuition and the Fuehrerprinzip over the German General Staff, establishing a trend which had led almost inevitably to the virtual dictatorship in military command exercised by the Fuehrer in 1944. Also, the contempt for Allied generalship which Hitler continually expressed can be regarded as more than bombast. He would be prone to believe that the Western Allies had learned nothing from the experience of 1940, that the conservative military tradition which had deemed the Ardennes as impossible for armor was still in the saddle, and that what German arms had accomplished in 1940 might be their portion a second time. Two of the factors which had entered into the plans for the 1940 offensive still obtained: a very thin enemy line and the need for protecting the Ruhr. The German attack could no longer be supported by an air force which outweighed the opposition, but this would be true wherever the attack was delivered. Weather had favored movement through the Ardennes defiles in the spring of 1940. This could hardly be expected in the month of November, but there is no indication that Hitler gave any thought to the relation of weather and terrain as this might affect ground operations in the Ardennes. He tended to look at the sky rather than the ground, as the Luftwaffe deteriorated, and bad weather-bad flying weather-was his desire. In sum, Hitler's selection of the Ardennes may have been motivated in large part by the hope that the clock could be turned back to the glorious days of 1940. 
 General Heinz Guderian, Panzer Leader (New York: E. P. Dutton & Co., Inc., 1952, app. 3.