Why the Allies Won

by Richard Overy

  The American army became in two years the most modern army in the world. Its air force followed the same course. Rather than concentrate on the single role of providing air support for the mechanised armies, the army air corps under General Hap Arnold began to plan in 1940 a multi-role air force, capable of strategic bombing, of large-scale air transport, of air defence and tactical air support. Aircraft were widely understood to explain Germany’s success in Europe. ‘Air power’, announced Secretary for War Stimson at the height of the Battle of Britain, ‘has decided the fate of nations; Germany with her powerful air armadas has vanquished one people after another.’42 American air intelligence exaggerated German air strength in 1940 by a factor of ten. Roosevelt needed little persuasion that the air force should be given everything it wanted. A new generation of bombers, fighters and fighter-bombers – the Flying Fortress and Liberator heavy-bombers, the B-29 Super Fortress introduced in June 1944 in the Pacific war, the Lockheed Lightning fighter-bomber, and the Mustang and Thunderbolt fighters – were all at the forefront of aviation technology, and were constantly refined as the war went on. They were produced in greater numbers than were needed, with generous spares and additional engines, to match what it was believed Germany was producing.43

  The development of a battlefield air force, designed to win local air superiority and to help push the ground forces forward, was a natural adjunct to the build-up of large mechanised armies. In 1941 the American air force began to experiment with close-support tactics. The results were very mixed, for there was no means for local army commanders to communicate directly with strike aircraft as there was in the German system. As a result air units responded slowly to demands for front-line assistance; messages had to be routed through major command posts, which was time-consuming and tactically ineffective. It was the system used by the RAF in France 1940 which American forces largely borrowed. When it was used in the North African campaign in 1941 and 1942 it proved a dismal failure. The solution arrived at was not dissimilar to Novikov’s reform of the Soviet air force that same year. The RAF placed mixed forces of bombers, fighters and fighter-bombers under a central tactical air commander who coordinated attacks closely with the requirements of the army command. At the front-line, mobile control centres, with radar and radio communications, kept contact with aircraft in the air and the army in front. The bombers attacked rear areas and disrupted communications; fighters kept the enemy air force at arm’s length; fighter-bombers attacked battlefield targets and tanks.44 These tactical changes were sufficient to blunt Axis air power in the desert, which had never been strong. In the weeks before El Alamein Rommel had a foretaste of the devastating air power he would witness in France – ‘the paralysing effect which air activity on such a scale had on motorised forces’. ‘Anyone’, he ruefully reflected, ‘who has to fight, even with the most modern weapons, against an enemy in complete command of the air, fights like a savage against modern troops …’45

  The American air forces assigned to the North African campaign were still in their tactical infancy. The cumbersome command structure that evolved in 1941 had predictable effects: army units found that air support took so long to arrive that there was little point in requesting it. Airmen and ground troops had difficulty distinguishing enemy from friendly forces. Attacks were made at the front-line, but little attempt was made to counter Axis air power in the rear, or to attack supply and reinforcement areas. The ability of ground and air to work in combination, which was central to the new form of warfare, was conspicuously absent. The humiliation in Tunisia forced a major reassessment of how American tactical air forces were employed. They were assigned to an independent central air command which worked in tandem with the army commanders. Their mission was to neutralise enemy air power first, then to attack supplies and troop movements, and finally to attack critical points on the battlefield. During the Italian campaign the system was improved with the introduction of ‘Rovers’ – pairs of air controllers and army liaison officers who literally roved the battlefield calling up fighter-bomber strikes – and ‘Horsefly’, a small light aircraft acting as a forward air controller for directing bomb attacks on enemy artillery and transport. By the time the Allies deployed overwhelming air power over Normandy they operated a sophisticated system of air-ground cooperation that could cope with everything except poor weather.46

  By the time the western Allies brought their mechanised armies and tactical air power to bear in France in 1944 much of the damage had already been done to German forces. The bombing offensive diverted and destroyed the better part of German air power, so that the tactical air forces had little or no opposition. They were free to roam far and wide over German-held areas, destroying equipment and vehicles in order to accelerate the decline in German technical resources. Bombing also interrupted the German supply of fuel, tanks and ammunition to the French front, making a difficult supply situation worse. When it was turned on the front-line itself, as it was on the Panzer Lehr division, it could turn the tide of battle. ‘Utilisation of the Anglo-American air force is the modern type of warfare,’ commented Rommel’s deputy, Friedrich Ruge. Under these circumstances the Allies could afford a higher margin of error than the enemy. The application of technological strength through air power compensated for the difficulties in turning civilians with little experience of military life into effective soldiers. Western forces preferred the bomb to the bayonet. German soldiers wrote disparagingly of the poor fighting qualities of American and British Empire troops, particularly at close quarters. The effective deployment of modern technology, against an enemy forced to fight with little air cover, few tanks and dwindling quantities of trucks and guns, made the difference between victory and defeat.

  The campaign in Normandy destroyed what was left of the German mechanised army after its mauling on the eastern front. The 7th and 15th armies facing the French coast relied for their mobility on 67,000 horses. There were only 14,500 trucks for the whole front, and severe shortages of fuel and tyres. During the fighting in Normandy half the horses were lost and most of the trucks.47 Out of 2,300 tanks only a hundred survived. The soldiers fought with declining mobility and firepower against armies overflowing with resources. ‘If I did not see it with my own eyes,’ wrote one German division commander, ‘I would say it is impossible to give this kind of support to front-line troops so far from their bases.’48 Hungry, exhausted, outnumbered in the air and on the ground, German forces none the less fought with all their traditional operational and tactical skill. Hitler expected them, like Japanese soldiers, to fight to the last man. Most did not, but they fought with a desperate competence as long as it was possible to do so. It is widely accepted that man for man, German forces were generally more skilled than the enemy, east or west, for most of the war. But it was a margin that narrowed each year as the Allies reformed and modernised their forces, and as the slow process of de-modernisation set in for large parts of the German army. When the Allies sat on Germany’s borders in January 1945 to deliver the coup de grâce, the technical gap was beyond redemption. The western Allies mustered 25 armoured divisions and six thousand tanks against a thousand German tanks; on the eastern front over fourteen thousand tanks faced 4,800 tanks and self-propelled guns. Soviet forces were backed by 15,500 combat aircraft against 1,500; the United States alone had 32,000 aircraft overseas.49 For Germany modern war had come full circle since 1939.

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  The war of engines, of aircraft, tanks and trucks, was a war run on oil. ‘Petroleum products’, wrote the American geographer C.F. Jones, in 1943, ‘are the blood of battles that bring victory.’50 The Axis states were at a profound disadvantage in fighting modern war because they largely lacked this critical resource. Over 90 per cent of the world’s natural oil output was controlled by the Allies. The Axis states controlled just 3 per cent of the output and 4 per cent of the oil-refining capacity.

  So vital was oil for modern industry and modern war that the Axis states were willing to fight to gain
control of it. The Japanese decision to attack the United States and Britain in 1941 was forced by an oil embargo that cut off from Japan 90 per cent of her supply. The prime target of Japanese soldiers and sailors in the drive southwards was the valuable oilfields of Borneo, Java, Sumatra and Burma, which produced more than enough oil to cover all Japan’s military needs. In 1942 Hitler’s drive into southern Russia, against the generals’ advice, was aimed at the even richer oilfields of the Caucasus which could provide four times the quantity of oil Germany had in 1941. When German soldiers reached the oil centre of Maikop, and threatened to cross the Caucasus mountains to Baku, German and Italian forces in North Africa were battling towards the Suez Canal and the oil resources of the Middle East beyond. Axis armies came close to achieving a geopolitical dream, the conquest of the oil-rich crescent from Trans-Caucasia to the Persian Gulf.

  Japan conquered her oil supplies; Germany and Italy did not. Without the oil of south-east Asia the Japanese war effort would have petered out. Though retreating oilworkers blew up or ignited what they could before the Japanese arrived, the damage was not irreparable. The Japanese expected to take two years to get oil production going again, but some of the fields were working within days. During 1942 the southern region supplied almost as much oil as Japan had imported from the United States before the embargo. Most of the oil was refined on the spot and absorbed into the battles in the south Pacific. This left the rest of Japan’s forces and the home economy short of oil throughout the war. The large home fishing fleet was ordered to convert to sail and abandon oil. Even naval ships were converted back to coal, though it reduced their performance. Every effort was made on the home front to cut back on civilian oil consumption, which by 1944 was a mere 4 per cent of the amount used in 1941. From 1938 Japan had pursued a programme to produce synthetic fuel from coal, a process already pioneered in Germany. Although production went ahead, precise details of how the processes worked were withheld by the Germans until January 1945. In the interim the grandiose pre-war plans to produce 14 million barrels of oil a year fizzled out in the general climate of shortages; the peak of synthetic production was reached in 1942, a mere 1.5 million barrels of poor quality fuel.51

  The one problem to which little thought had been given was how to transport oil safely around the new imperial seaways. There was a large tanker fleet, to which 1 million tons of new tankers were added during the war. By the end of the war most of them were on the ocean bed. Knowing how much Japan depended on oil, American submarines and dive-bombers sought out the vulnerable tankers, which had virtually no protection, sailing in ones or twos. If they radioed for air protection they were more likely to be visited by American aircraft than Japanese, directed to the target by the regular interception and decoding of Japanese messages. The flow of oil to Japan’s empire began to slow down early in 1943; it was no more than a dark trickle by 1945.52 Too late, efforts were made to sail in large convoys, but even these were given little air or naval protection. On 9 January 1945 Commander Kuwahara led a slow convoy of tankers and merchantmen out of Saigon harbour, with six armed escorts. The following day it was spotted by a B-24 bomber. On the 12th it was ambushed by 16 fighter-bombers in mid-morning; one freighter was destroyed and the convoy was scattered. As it began to regroup seventy dive-bombers appeared, circling round the ships like hungry birds of prey. They bombed and torpedoed the convoy until dusk. All the oil tankers were sunk, all the merchant ships destroyed, and three escorts lost. The remaining escorts, heavily damaged, limped into harbour, where they were attacked and damaged three more times by carrier aircraft. Kuwahara survived, but of the convoy that followed from Saigon on the 10 January not one ship got through.53

  Japan’s oil situation was critical in 1944. Imports dropped to less than one-seventh of the pre-war volume. Though enough oil had been stockpiled to provide an estimated eighteen months’ supply, it was eaten away in the months of fierce fighting in the southern islands. By 1945 imports were almost zero, and stocks fell to a level so low that the fleet could no longer operate. During 1944 Japanese warships were hampered by fuel shortages from fighting effectively. They were forced to sail slowly to conserve oil, or to sail by direct routes when good sense called for evasion. Pilots could not be fully trained for want of scarce high-octane fuel, and pilot losses reached levels so high in 1945 that there was little to distinguish the regular flyers from the suicide squads. During 1945 thousands of aircraft and small suicide boats or shinyo – wooden vessels of 2 tons, driven by a truck engine, and primed with high explosive – were gathered in Japan for the last-ditch defence of the home islands. They needed little fuel, and there was little to be had. The last barrels of carefully hoarded oil were hidden in caves and storerooms to power the suicide forces on their one-way passage.54

  In Germany the decision was taken long before the war to find a substitute for natural oil. Although Germany produced a small quantity of oil from her own wells – about one-fifth of German consumption in 1939 – most German oil, like Japanese, came from the New World in the 1930s. One resource Germany did have in abundance was coal. In 1909 the German chemist Friedrich Bergius discovered a way of producing oil from coal by combining it with hydrogen under pressure. The process was known as hydrogenation. Though Bergius could produce oil in the laboratory, he could not find a way to extract it in quantity. During the 1920s the German chemical giant IG Farben bought up the Bergius patents and began a long and costly attempt to produce synthetic oil commercially. Though oil was produced in quantity it proved impossible to market: the synthetic material was six times more expensive than natural oil.

  The project was saved by Hitler and the German armed forces. Even before Hitler came to power in January 1933, he had met with directors from IG Farben to assure them that a Nazi government would do everything to promote hydrogenation in order to render Germany immune to the threat of embargo or blockade. The new German armed forces in the 1930s needed oil as a top priority. In December 1933 the Hitler government signed a deal with IG Farben: the state promised to subsidise synthetic oil if the company committed itself to a four-year oil project. In 1936 the regime finally set up a programme to make Germany virtually independent of external sources of oil if war broke out. The programme was boosted by the seizure of the Sudetenland from Czechoslovakia in 1938, for the Sudeten areas contained rich deposits of lignite, or brown coal, which was far more suitable for synthetic production. By 1939 Germany produced just over one-third of her oil needs; by 1943 the figure was well over 7 million tons, three-quarters of all the oil she used.55 Almost all the requirements of high-octane aviation fuel were met from the synthetic plants. What could not be produced at home was supplied from the Romanian oilfields at Ploesti, once Romania had become a virtual satellite of the Third Reich in 1940. Small quantities – about 10 per cent of German consumption – were provided in 1940 from the Soviet Union under the terms of the Nazi-Soviet Trade Agreement of 1939.56

  If Germany had enough oil to fight with, the margin was slim indeed. The home front was starved of oil. Cars and lorries were compulsorily converted from petrol-driven to gas-driven motors. Those still permitted for non-military use were driven through the streets with large canvas gas bags attached, like so many small Zeppelins. The horse once again was in demand to haul goods and supplies. German inventors scoured Europe’s flora for fuel substitutes. The acorn harvest, traditionally fed to pigs, was commandeered to produce a usable oil which was capable of fuelling haulage vehicles. European nuts were transformed chemically into a good-quality fuel to be used in tanks and trucks, and the residue was used as cattle-feed. A rich yellow oil, good to smell and taste, was pressed from the grape waste of French vineyards and was used as a machine lubricant.57 None of these expedients could cope with demand from the armed forces and from industry. Fuel shortages slowed up progress in Russia in 1941; Rommel in North Africa was plagued by oil supply problems, though Axis forces drove back and forth across the undiscovered oilfields of Libya. While Allied forces could
draw on the oil supplies of the Middle East, delivered by pipeline to the eastern Mediterranean, Axis oil supplies had to be carried on the dangerous convoy routes to Libya and Tunisia. They then had to be transported long distances from the ports with a severe shortage of tankers and trucks, under increasing air attack. Low mobility restricted the Axis drive to capture the very oil they needed.58

  The alternative to acorns and nuts lay in the large oilfields of southern Russia. It is arguable how important oil was when Hitler planned Barbarossa. But by the winter of 1941–2 the oil question was central. The assault on Moscow was held up for six weeks while Hitler insisted that the drive to the Caucasus had priority. In the event neither was captured, but Hitler was convinced, against the forceful protests of his generals, that the oil question could decide the war. The capture of the Caucasus would kill two birds with one stone: the Soviet armies would be deprived of the oil needed to fight, and Germany would capture the oil she required to combat Britain and the United States. Hitler’s directive for the summer campaign of 1942, Operation Blue, published on 5 April, placed the main weight of the German offensive in the south, ‘in order to secure the Caucasian oilfields’.59 By July German forces had swept through the Crimea and across the Don and were within striking distance of the first oilfields and the Soviet oil lifeline up the Volga, past Stalingrad.