Guderian came to his position from his experiences in the east with the Red Army, Rommel from his experiences in Africa with the western Allies. They proposed diametrically opposite solutions.
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Panzer and panzergrenadier divisions, Guderian wrote, “must be stationed far enough inland from the so-called Atlantic Wall so that they could be switched easily to the main invasion front once it had been recognized.”
Guderian and Geyr proposed that the ten fast divisions Hitler had allocated to defend the west be concentrated in two groups, one north and the other south of Paris. Both officers recognized the immense superiority of Allied air power, and that it gravely affected German ability to shift armor. But they believed the problem could be overcome by moving at night.
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Because of Allied air supremacy, Rommel said, there could be no question of moving large formations, even at night.
To Rommel the day of mobile warfare for Germany had passed, not only because of Anglo-American air power but because Germany had not kept up with the western Allies in production of tanks and armored vehicles—a result due more to the shortage of oil than to Allied bombing.
Implicit in Rommel’s theory was that the Germans must guess right where the Allies were going to land. If German forces could not move, they had to be in place close to the invasion site. Rommel decided that the Allies would land at the Pas de Calais opposite Dover.
Rommel ruled out other landing places, especially because the Allies could provide greater air cover there than anywhere else. Rommel wrote Hitler on December 31, 1943, listing the Pas de Calais as the probable landing site. “The enemy’s main concern,” he wrote, “will be to get the quickest possible possession of a port or ports capable of handling large ships.”
Guderian did not conjecture precisely where the Allies might invade. He thought they should be allowed to land and make a penetration, so that their forces could be destroyed and thrown back into the sea by a counteroffensive on a grand scale. This was in keeping with successful German movements in Russia. Although Rundstedt and Geyr accepted the idea, neither they nor Guderian had any idea how Anglo-American command of the air could restrict panzer movement.
Rommel did, and to him Guderian’s proposal was nonsense. “If the enemy once gets his foot in, he’ll put every antitank gun and tank he can into the bridgehead and let us beat our heads against it,” he told General Fritz Bayerlein, commander of the Panzer Lehr Division.
The only way to prevent this, Rommel wrote, was to fight the battle in the coastal strip. This required operational reserves close behind the beaches that could intervene quickly. Bringing reserves up from inland would force them to run a gauntlet of Allied air power, and take so much time the Allies could organize a solid defense or drive farther inland.
Rommel set about building a fortified mined zone extending five or six miles inland. He also built underwater obstacles along the shore—including stakes (“Rommel’s asparagus”) carrying antitank mines, concrete structures equipped with steel blades or antitank mines, and other snares. But his efforts came too late to be fully effective, and they were concentrated in the Pas de Calais, though some work extended to Normandy.
Rommel and Guderian were both wrong, of course. The Allies were not bound to take the shortest route to seize the closest port. Rommel did not understand the vastness of Allied maritime resources, and he was not aware of British ingenuity in building two artificial harbors (Mulberries) which could serve as temporary ports. The Mulberries veiled the biggest secret of all: the Allies did not have to capture a port to invade the Continent. This made possible a landing at the least likely place still under the Allied air umbrella: the beaches of Normandy.
Guderian was wrong in his belief that the Germans could duplicate anything like the vast sweeping panzer movements they practiced in Russia. There the Luftwaffe generally had parity with the Red air force, and could achieve temporary local superiority to carry out a specific mission. In the west, Allied air power was overwhelming and permanent.
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Erich von Manstein had won the campaign in the west in 1940 by convincing Hitler to concentrate his armor. Now, at the moment of Germany’s greatest military peril, Hitler was dispersing his armor—all across the map. Furthermore, he kept a firm rein on most of these divisions, intending to direct the battle from Berchtesgaden.
If, instead, three or four fast divisions had been stationed directly behind the beaches at each of the potential sites, they very likely could have crushed any invasion on the first day.
When I was at Ohio State, I served with a former Luftwaffe pilot, Joseph Treiterer, who had flown ME 109’s in No. Africa and was on Rommels’s staff in France. He never talked about the war, but one evening at a faculty party an American who served in China was bragging about his service medals, and Joe said, “I have medals, too.”
Determining WHERE the main effort of the allies was to be an important factor for the German. That deception campaign of the allies to fool the German continued for a month or month or more after the Normandy landings.
Time and place of their own choosing very much on the side of the allies.