The Bombing War: Europe 1939–1945

by Richard Overy

  Civil defence regimes everywhere in the 1930s depended on some level of popular participation. One of the implications of total war waged by bomber aircraft was the need for home populations to recognize that they would become, willy-nilly, a home army combating the effects of air raids. Levels of participation, not all of it voluntary, varied from state to state. In Germany and the Soviet Union, mass organizations were created – 13 million in the German Air Defence League (Luftschutzbund), founded in 1932, 15 million in the Soviet Osoviakhim, established in 1927. Neither organization was a formal civil defence service, but they provided propaganda and training for householders, students and workers. In both cases there was a strong ideological imperative to join, in the Soviet case to help preserve the new revolutionary state, in the German case to defend the National Socialist ‘People’s Community’. In other states there was greater reliance on volunteers for regular civil defence services, medical aid and welfare, but these numbered millions by the end of the 1930s. A conservative estimate of the number of Europeans involved in some form of civil defence activity by 1939 is somewhere between 30 and 32 million, the great majority German and Soviet. The motives for joining evidently varied widely. If some were motivated by apprehension at what the air war would be like, it seems more plausible that those who became full-time or part-time civil defence workers did so because they believed it was possible to ameliorate the physical and social effects of bombing, despite rather than because of the lurid images of its unbearable nature. A proportion was almost certainly animated by the ideology of community protection, though some, like the British novelist Henry Green, joined in order to avoid having to serve in the army.67 A great many became civil defenders simply because of where they worked and lived.

  The sense that here were urban communities about to become embattled reinforced the argument that in the next war whole societies would be on the front line. This did little to allay the anxieties about air warfare. Civil defence preparations could be seen as a rational response to threat, but they could also be seen as a sure indication that bombing and gassing were going to happen. In Germany by the late 1930s the civil defence authorities found evidence that side by side with community civil defence commitment there existed persistent anxiety and scepticism about the dangers to which the population was now exposed and the deficiencies of existing provision.68 In Britain, popular reaction to increased civil defence activity provoked hostility from anti-war and pacifist lobbies which saw air-raid precautions as an invitation to militarize the nation and evidence that the government was preparing for war. The No More War Movement encouraged its members to acts of civil disobedience against civil defence requirements because they represented ‘the psychological preparation for rearmament’. In December 1937 the National Peace Council, the umbrella organization for all pacifist and anti-war groups, agreed to investigate the establishment of ARP Vigilance Committees in every city to challenge the implicit militarism of civil defence measures and to argue that peace was a surer path to security. Some local boroughs with left-wing councils refused to introduce civil defence measures until compelled to do so during the early months of war.69

  Much criticism was also levelled at what was seen as a deliberate failure on the part of government to provide even the minimum level of shelter and security.70 Scientists and architects regularly recommended radical, if idealistic, responses to the air threat. In 1938 Frederick Towndrow, the editor of Architectural Design and Construction, argued in an article on ‘The Great Fear – And After’ for a systematic programme of urban decentralization, bomb-proof plans for building, and a network of bunkers and arterial roads underneath every city.71 Another proposal published in 1937 for building 100 new small towns designed to limit the air threat recommended broad boulevards, wide recreational spaces (useful for segregating parts of the town ‘which might happen to be on fire because of incendiary bombs’), and residential housing built around quadrangles to prevent the spread of gas and allow easy escape onto the street.72 In Germany in the late 1930s all new residential housing was supposed to have an air-raid shelter built into its design, while plans were also elaborated for decentralizing the population into small towns of 20,000 people, or even in isolated homesteads, one for every four acres of territory.73 In France, fantastic schemes were sketched out against the air threat, including an air defence skyscraper more than five times the height of the Eiffel Tower, with platforms for anti-aircraft guns, observer posts and fighter aircraft, and an underground city of the future, its subterranean structure covered over with earth to allow farming to carry on above the sunken streets.74 The integration of civil defence into thinking about town planning and construction provides a further illustration of the extent to which the expectation of future air war had become embedded in popular European culture by the late 1930s.

  There are several possible ways to interpret the popular and political response to the bombing threat, either as prudent forethought or the product of an over-anxious imagination or a fatalistic acceptance of the unavoidable terms of modern conflict. Apprehension was not all fantasy, since modest bomb attack had already been experienced in the Great War, but that experience came to be distorted through eager extrapolation. All the popular and political responses to the air threat in the Europe of the 1930s shared a collective understanding that bombing would be a characteristic of future war, that it would involve assault on civilians and civilian life, that it would be aimed principally at cities and that it would involve destruction at a level likely to induce social chaos. Unlike most military revolutions, where change is generated within the military environment, the bombing war took shape first in the public imagination, where it was incubated under the glare of public anxiety long before most air forces had either the means or any doctrinal interest in creating a strategic capability aimed at the heart of an enemy nation. Air forces were bound to be affected by the way in which future war was framed in public discussion, because air power was at the centre of all the predictions about how catastrophic the next war would be. The attention given to air power flattered the infant air forces and inflated the desire for organizational autonomy and a strategic profile distinct from the other two services. There remained nevertheless a wide gap between the air war as it was popularly imagined and the evolving strategic outlook of the air forces themselves.

  There were many factors inhibiting the development of a bombing strategy. For most of the interwar period air forces had to struggle to secure enough money to be able to construct the necessary infrastructure for the exercise of air power and to be able to keep abreast of a rapidly changing technology. At the same time the persistent calls for air disarmament, even for the abolition of all military aircraft, compelled air force leaders to spend time and effort simply trying to retain any military capability at all. Political effort also had to be devoted to contesting the aim of armies and navies to rein back air force ambitions for independence and to compel air forces to think principally in terms of support for surface forces. ‘The decision in war devolves to the forces on the ground,’ wrote one German commentator on the air force experience in the Spanish Civil War, ‘and on the forces that fight on the ground, not in the air or from the air.’75 In the United States there remained persistent hostility from the army to the claims for air force independence and a strategic bombing force. Commenting on the Italian war effort in Ethiopia in late 1935, Deputy Chief of Staff General Stanley Embick concluded that air power was secondary: ‘Italian progress from day to day is measured solely by the slow advance of the men in the mud … the role of military aviation must by its inherent nature be essentially of an auxiliary character.’ In his view, the claims made for air power were exaggerated and unrealistic: ‘They [aircraft] are fragile, vulnerable to the smallest missile, inoperable in bad weather, and exceedingly costly.’76 In France the air force remained closely tied to the army, even after a measure of organizational independence was conceded in 1933. Some 86 per cent of all French aircraft remained at
tached to individual army units, at the disposal of army commanders.77

  The most difficult problem confronting airmen after 1919 was the unstable and rapidly evolving nature of the air weapon. The gap between the biplanes and triplanes of 1918 – slow, cumbersome, easily damaged craft made of wood and wire – and the faster monoplane, metal-framed and heavily armed aircraft of 1939, was a quantum leap in technology. It was essential, given limited budgets and little practical experience, that right choices be made when modernizing an air force. Since the technology changed almost year by year, overcommitment to a particular aircraft model or strategic profile could prove costly; with such a potentially unstable technology, obsolescence was a high risk and security uncertain. This was no more evident than in the shifting balance between offensive and defensive air power. By the late 1920s light bombers were as fast, or faster, than the biplane fighters that might intercept them; by the late 1930s high-performance monoplane fighters were more than 100 miles per hour faster than the light and medium bombers they opposed, capable of much greater manoeuvrability and with powerfully destructive armament. In almost all major European states radar detection of incoming enemy aircraft was either operationally available or in the process of development. As the balance shifted towards defence, air forces had to choose carefully the kind of bomber aircraft they should now invest in. This perhaps explains the designation of ‘Ideal Bomber’ given by the RAF when it began to search in 1938 for a heavy aircraft (specification B19/38), capable of long range, a heavy bombload, and flying high enough and fast enough to be less troubled by enemy fighter aircraft.78 In the end, the project remained idealistic: the bombers that the RAF relied on for its later offensive were twin-engine bombers hastily converted to a multi-engine heavy-bomber role in the first years of war.

  Most air forces between the wars opted to develop battlefield light- and medium-bomber aircraft, supported by ground-attack fighter-bombers, rather than pursue the strategic aim of the ‘knockout blow’. This was true even in Douhet’s Italy, where the air force rejected mass fleets of bombers in favour of a variety of assault aircraft to support surface operations.79 This choice depended to some extent on the prevailing role of the army in overall military planning and the army’s belief that the most strategically efficient use of air power was in some form of combined arms operational structure. In France, Germany and the Soviet Union there existed a core of airmen who did favour an independent strategic air force, based around a bombing capability, but they lacked sufficient prestige or influence to overcome the preference of the ground army to exploit air power as an important adjunct to any ground campaign or the opposition of those airmen who thought air defence and air-to-air combat a better use of scarce resources.

  In France, the armed forces were strongly influenced by the experience of the Great War, which seemed to demonstrate clearly that overwhelming air power on or near the fighting fronts was more strategically decisive than speculative long-range bombing of the enemy home front. The main statement of French bombing theory by Camille Rougeron, L’Aviation de Bombardement, argued that the ideal bomber aircraft should be derived from fighter design and be used both to attack military targets and to win air superiority over the battlefield.80 The 1921 French Instruction for the armed forces laid down the principle that air power should be used in support of front-line operations. In 1936 the Instruction was modified by the Popular Front Air Minister, the radical left-wing politician Pierre Cot, to allow for the creation of an operationally independent strategic reserve. But even this reserve was designed to allow for mass attacks at critical points in the battle either to disrupt enemy supplies and reinforcements or to make possible a breakthrough on the ground. When Cot lost office in 1938, the strategic reserve was once again broken up and distributed among the defending armies along the French eastern frontier.81 The French Army deeply distrusted Cot and his sympathy for the Soviet Union and came to identify his policy of independent, strategic air power as a Communist attempt to subvert the role of the army in determining French military doctrine. The ‘strategic’ use of air power was regarded as simply an extension of the main battle, not as an alternative.

  In practice, aviation in the Soviet Union moved closer to the French model during the 1930s. In the late 1920s, when the Red Army began to think seriously about future strategy, the idea of creating a mobile strategic air reserve for use at critical points in the battle, or for effecting a breakthrough for the ground army, became accepted doctrine. Under the influence of two Soviet air theorists, A. N. Lapchinskii and Vasily Khripin, encouragement was given to the establishment of independent bomber units. In 1935 these were grouped together into a strategic reserve, aviatsya osobovo naznachenya (AON), but like Cot’s plan, the object was to use them at critical stages of the ground battle. Some thought was given to the possibility of bombing distant targets in Germany or Japan in the event of war, but the thought was never enshrined in doctrine. In 1937 Stalin ordered an end to the heavy-bomber programme, partly because of the poor safety record of the aircraft, but largely as a result of the military purges in 1937 which decimated the group of army and air force leaders who favoured independent strategic operations. Priority was given thereafter to ground attack and medium-bomber aircraft designed to give direct support to ground armies. In 1940 AON was broken up and, like French bomber aircraft, redistributed to front-line army units.82

  The German case proved to be similar, except that Germany’s compulsory air disarmament after the Versailles Treaty of 1919 postponed the formal development of German air power until the advent of Hitler as chancellor in January 1933. In the absence of an air force, the War Ministry in the early 1920s established more than 40 study groups dedicated to evaluating the lessons of the earlier air war, but only four looked at bombing. Their conclusions shaped subsequent German air strategy. Aircraft were judged to be a primarily offensive weapon, and the principal object of an aerial offensive was the achievement of air superiority over the battlefront.83 Long-range bombing of the enemy home front was not regarded as strategically worthwhile, partly because anti-air defences were expected to be able to blunt an air offensive, partly because it would disperse rather than concentrate a combined arms offensive. Among the former air force officers working in the War Ministry in the 1920s was a small group who favoured developing a more strategic role for a future air force, including Lieutenant Colonel Helmuth Felmy and the future chief of the air staff in 1935, Colonel Walter Wever. But even under their influence, the air force operational doctrine published in 1935 on ‘The Conduct of the Air War’ emphasized that the chief objective of the air force was to support the army’s ground operations and to eliminate enemy air power, followed only if necessary by attacks on enemy war production to break a front-line stalemate: ‘The will of the nation finds its greatest embodiment in its armed forces. Thus, the enemy armed forces are therefore the primary objectives in war.’84

  This remained the central principle of German air force doctrine and it owed much to the fact that almost all the senior airmen responsible for shaping air strategy, including the commander-in-chief and former Prussian army cadet, Hermann Göring, originally came from a conventional army background, in which concentration of all available force on the battlefield mission was expected to be decisive. ‘In the war of the future,’ wrote Wever, echoing the doctrine laid down in 1935, ‘the destruction of the armed forces will be of primary importance.’85 The German Air Force Service Manual in 1936 excluded the use of aircraft in terror raids on cities in favour of bombing attacks on the depots, communications and troop concentrations deep in the enemy rear.86 German airmen were confident that a network of high-quality anti-aircraft guns and searchlights, supported by defensive fighters and a system of effective communication, could prevent a bomber offensive from inflicting serious damage on Germany’s war effort, either in the zone of battle or on the home front.87 The experience of the German Condor Legion in the Spanish Civil War (which provided almost three years of practical c
ombat, ideal for the refinement of the close-support strategy) confirmed the air force argument that front-line aviation made most strategic sense and that attacks on an amorphous target like morale were just as likely to be counter-productive by strengthening resistance.88 Unlike the RAF, German airmen drew from the lessons of the Great War the conclusion that it made much more strategic sense to fight the enemy air force and to protect the ground army rather than squander men and machines on long-range bombing. The ‘knockout blow’ was to be inflicted at the battlefront, an intention dramatically fulfilled in all the German campaigns from Poland in 1939 to the Soviet Union in 1941.