Once the immediate shock had passed, the search for explanations began. Why had Napoleon’s heirs fallen so quickly? Many Frenchmen chose to blame insidious Fifth Columnists: Nazi and Communist agents who had supposedly undermined the homeland from within. (Nazi Germany and the Soviet Union were allies at this point.) Visiting Paris in May 1940, Clare Boothe heard constant talk of trahi (betrayed): “At first it was no more than a whisper…. And then the whisper became a great wail that swept through France, a great wail of the damned: ‘Trahi…trahi….’” Although a number of people were lynched as suspected enemy agents, in reality there were few German spies operating behind enemy lines, and their meager efforts can hardly explain the magnitude of the disaster that befell France.
A more plausible version of the “stab in the back” thesis was that France was undone not by active treason but by passive indifference: Following the carnage of the Great War and two decades of political turmoil pitting right against left, the French had simply lost the stomach to fight another costly war. This theory was widely held by those who participated in the actual events, but it has met with skepticism from modern historians who point to contemporary records showing that French morale had made a considerable recovery by the time Germany invaded Poland in September 1939. Hitler’s aggression convinced most French people of the rightness and necessity of war. They were “resigned but resolute,” in the words of the British ambassador. And in the war that followed, while some French units crumbled without a fight, many others fought hard even while suffering crushing casualties. In six weeks of combat, France lost an estimated 124,000 men killed and 200,000 wounded, more than the American casualties in the Korean and Vietnam Wars combined over the course of many years.
Even more damning to any attempt to ascribe France’s defeat to its loss of will is the fact that morale on the other side was by no means as high as a zeppelin. Many Germans were as reluctant to fight as the French, not least among them generals who were so afraid that Hitler was leading them to disaster they had discussed mounting a coup to topple him. Only with the successful conclusion of the campaign against France did real enthusiasm for the war break out in Germany. French spirits would have been equally ebullient if their soldiers had won any victories to boast of. The low state of morale among the French cannot be entirely dismissed as an explanation for their downfall; there is no denying that most Frenchmen did not fight till the bitter end and that few joined the Resistance or the Free French forces. But the dominant view of recent historians is that the French loss of will was more the consequence, rather than the cause, of battles lost.
Why, then, did the Germans win those battles? The prevalent impression of the time—that the Allies were outnumbered—is false. As we have seen, the Allies enjoyed an advantage in the overall number of divisions, tanks, aircraft, and artillery pieces. The one critical area where they were deficient was in the number of bombers and fighters actually deployed on the Western Front. The Germans had 2,779, the Allies 1,448. But this was not due to some inherent deficiency on the Allied side; it was mainly because the British and French did not commit many of their aircraft to the fight. The British understandably chose to keep the bulk of their air force at home for self-defense. Less understandable, indeed inexplicable, was the French decision to keep many of their planes in southern France and North Africa, where they could do no good. The problem, in sum, was not how many aircraft the Allies had but how they were utilized.
Another popular misconception—that the Germans had superior weapons—does not stand up to scrutiny either. The best tanks belonged to the French, not the Germans; the best Allied aircraft were as good as the best German models. The only technical area where the Germans had a major edge was in their widespread use of radios, which gave them operational flexibility and the ability to concentrate their mechanized forces and warplanes at the decisive point of attack. This made up for the fact that the vast bulk of their troops walked to the front. (Out of more than one hundred German divisions mobilized for the campaign in the West, only ten were tank divisions and another ten were motorized.)
If the Germans did not have material superiority, what accounted for their easy victory? Quite simply, their decisive edge in doctrine, training, planning, coordination, and leadership. Writing in 1942, two years before his death,
Marc Bloch convincingly argued that “the German triumph was, essentially, a triumph of intellect.” The Germans had adapted their methods of warfare to the Second Industrial Revolution, which had transformed “the whole idea of distance.” The French had not. “The ruling idea of the Germans in the conduct of this war was speed. We, on the other hand, did our thinking in terms of yesterday or the day before. Worse still: faced by the undisputed evidence of Germany’s new tactics, we ignored, or wholly failed to understand, the quickened rhythm of our times. So true is this, that it was as though the two opposed forces belonged, each of them, to an entirely different period of human history.”
Still, there was nothing inevitable about the outcome. “As I looked at the ground we had come over,” Guderian wrote, “the success of our attack struck me as almost a miracle.” It is not hard to fathom why even this most self-confident and swashbuckling of generals would be agog at his own success. It could easily have gone the other way, especially if the Germans had stuck to their original version of Case Yellow or if something had gone wrong during their journey through the Ardennes or across the Meuse. That the Germans prevailed so quickly owes something to luck and even more to their meticulous preparation and inspired execution. While the daring use of panzers got most of the attention, the key breakthrough was due to courageous infantrymen rowing across a river under fire—a maneuver that the Germans had practiced meticulously beforehand on the Moselle River. When the time came for the actual crossing, Guderian was able to issue the same orders used in the exercises with only the dates, times, and locations changed. Thus the final victory was a tribute not to panzers alone but to the skillful employment of the combined-arms concept.
From a historical perspective, the German victories in Poland, Norway, Denmark, Belgium, Holland, and, above all, France helped to reestablish the possibility of the decisive campaign. The ability to achieve clear-cut results on the battlefield had been in decline since the mid-nineteenth century, when the firepower and sheer size of armies had increased beyond the ability of transportation and communications networks to cope. Generals could barely find their foes (recall how blind both Moltke and Benedek were on the eve of Battle of Königgrätz), much less maneuver effectively to destroy them. Faced with machine guns or even rifles, cavalry could no longer perform its traditional role of hunting down and destroying the tattered remnants of defeated armies. This meant that the losing side on the battlefield could usually make good its escape, as Lee did after Gettysburg, and return to fight another day. The growing indecisiveness of war reached its apotheosis in World War I, where, on the Western Front at least, combat became a senseless struggle for a few yards of ground. Now, with the rise of mechanized forces, the art of maneuver could once again be practiced as skillfully as it had been by Frederick the Great or Napoleon Bonaparte. With their lightning victories, Hitler’s legions had shown that force of arms could win wars, not just battles. Or so it seemed in 1940.
In the warm, heady afterglow of victory, the Germans tended to forget all the doubts that had plagued them before and during the invasion of France. More and more generals joined Hitler in concluding that their war machine was invincible and unstoppable. Not even their failure to knock Britain out of the war could disabuse them of this illusion. Weakened by its losses over France, the Luftwaffe could not establish air superiority over southern England in the summer and fall of 1940, and Hitler had to call off his planned invasion, Operation Sea Lion. Germany returned to the path of conquest in 1941 with the swift occupation of Yugoslavia and Greece. Rommel’s Afrika Korps also enjoyed steady success in North Africa against British forces from the time of its arrival in February 1941 until the battle of El Alamein in October 1942. By then Rommel’s operations had become a mere sideshow to the much larger war being fought in Russia.
Hitler invaded the Soviet Union on June 22, 1941, with 3.2 million soldiers, 3,600 tanks, and 700,000 horses. No matter that he faced an enemy with millions more men, three times more aircraft, and five times more tanks. His armies enjoyed swift and stunning success against the ill-prepared Russian troops deployed on the frontier. The Soviet tank and air forces were almost completely annihilated. The Nazis advanced deep into Russia, arriving on the doorstep of Leningrad and Moscow by the winter of 1941. Then the offensive stalled out, partly as a result of stout Soviet resistance but mainly due to the inherent limitations of the Wehrmacht.
The blitzkrieg had proved a devastating weapon in the relatively confined spaces of western Europe. Its force was considerably dissipated on the nearly endless steppes of Mother Russia. Warfare in the Second Industrial Age required moving not only tons of food and ammunition but also tons of fuel and lubricants to keep tanks and trucks on the go. German logisticians were simply not able to keep their armies supplied more than a few hundred miles beyond the frontier (Sedan to Dunkirk is 170 miles); in Russia, German armies quickly found themselves more than a thousand miles from their bases.
These difficulties were compounded by the onset of the harsh Russian winter, for which the Nazis had not prepared; they had expected the entire campaign to be over in four months. The Germans found themselves trapped deep inside Russia, freezing, hungry, exhausted, running low on fuel and ammunition, and facing an adversary that was growing stronger by the day. The turning point was the Battle of Stalingrad. By the time it was over in January 1943, the Germans had lost 209,000 men killed and 91,000 captured. Hitler tried one last major offensive at Kursk in July 1943. His forces were repulsed in the largest battle of the war, pitting more than two million men and six thousand tanks against each other.
The Soviet victory at Kursk represented a hard-won armored renaissance. The Russians had been among the leaders in developing mechanized forces in the 1920s and early 1930s. Under Marshal Mikhail Tukhachevsky, they had invented the doctrine of “deep battle,” a variant of blitzkrieg, which called for masses of tanks and airplanes to penetrate hundreds of miles behind the enemy’s front lines to isolate and encircle opposing forces. In 1937, Stalin had executed Tukhachevsky in his purge of Red Army officers. The “deep battle” doctrine was discredited along with its founder, only to be revived in 1942–43 after the Soviets had suffered severe setbacks at the hands of Nazi tank forces. On the Eastern Front, then, the Germans eventually faced an adversary that fought much as they did—only with far more men and tanks and airplanes to throw into the fray.
The same thing happened in the West. The fall of France alerted Britain and America to the need to develop better mechanized forces. The U.S. had deployed a Tank Corps in World War I, but it was disbanded in 1920 over the anguished objections of two of its leading officers—Colonel George S. Patton and Major Dwight D. Eisenhower. In the interwar years, the U.S. Army spurned the innovative American tank designer J. Walter Christie, who sold his work to Russia, where it formed the basis of the workhorse T-34 tank. In the 1930s the U.S. Army limited its mechanization to one cavalry brigade. The first armored divisions were not formed until after the fall of France, in July 1940. They were tested in war games in Louisiana and Tennessee in 1941, and dispatched the following year to fight in North Africa. U.S. troops did not perform well at first, but by the time of the Normandy invasion in 1944 the U.S. possessed formidable armored forces grouped into all-arms divisions equipped with the serviceable if not spectacular M4 Sherman medium tank and led by generals like Patton whose abilities rivaled those of Rommel and Guderian. And, unlike the Germans, the Americans managed to motorize most of their army, rather than just its spearhead.
The British, likewise, fielded effective armored forces after the fall of France, starting with the 7th Armored Division, which under the tank pioneer General Percy Hobart thrashed Italian troops in North Africa in 1940–41, and continuing on to the much larger forces under Field Marshal Montgomery’s command during the drive into Germany in 1944–45.
Despite the considerable achievements and painful sacrifices of the Allied armies in their quest for victory, the Germans ultimately did not lose the war because they faced forces superior in the quality of men or materiel. The Panzer V (Panther) and Panzer VI (Tiger), developed in 1942, were probably the best tanks of the war; Sherman tank rounds would simply bounce off their frontal armor, while they could wreck a Sherman with one shot.
The German soldier, too, was in all likelihood the best of the war. A postwar study by Trevor Dupuy, a retired U.S. Army officer, found that, right up until the end, German units had at least a 20 percent “combat effectiveness superiority per man” over Anglo-American forces, meaning that “[o]n the average, a force of 100 Germans was the combat equivalent of 120 American or 120 British troops.” The German advantage over the Russians was even greater. According to Dupuy, one hundred German soldiers were the equivalent of two hundred Russians. While Dupuy’s findings have been questioned, there is little doubt that the Germans were at least as effective as their enemies, if not more so.
But few armies, no matter how effective, can prevail when outnumbered as badly as the Germans were by the later stages of World War II. They faced a crippling deficit not only in manpower but also in materiel. As early as 1942, the United States was outproducing all of her enemies combined—in historian Richard Overy’s summation, “47,000 aircraft to 27,000, 24,000 tanks to 11,000, six times as many heavy guns.” Add in Soviet production, which recovered rapidly after the catastrophes of 1941, and the disparity became almost insuperable.
The Allied weapons may not have been as technologically sophisticated as some German models, but they were cheap, durable, and plentiful. Henry Ford, with his mass production techniques, was more valuable to the Allied cause than any general: “The Ford company alone,” Overy notes, “produced more army equipment during the war than Italy.” The Allies also had access to vast pools of natural resources that the Axis could not match; most critically, they controlled 90 percent of the world’s natural oil production.
If the Allies had fought as incompetently as they had in 1939–41, they might have frittered away these considerable material advantages. Luckily for them, by 1943 their tactical skills had improved enough—if still not perhaps to the German level—to make effective use of the products being churned out by their factories.
This goes to show the limits of a military revolution. If Hitler had possessed the sagacity of a Bismarck and made peace following the victories of 1939–40, as Bismarck made peace following the victories of 1864, 1866, and 1870, he might have consolidated the conquests won by his peerless war machine. By choosing to push the blitzkrieg farther than it could reasonably go—by taking on both the U.S. and USSR—the Führer consigned Germany to a war of attrition that it would have been hard-pressed to win, unless, perhaps, it had developed a true wunderwaffe (wonder weapon) like the atomic bomb. (Hitler’s ersatz wonder weapons, the V-1 cruise missile and V-2 rocket, were not enough.)