Opinions on Bomber Command are like belly buttons – we’ve all got one.
Whether your knowledge is limited to having watched The Dambusters on a rainy Saturday afternoon, or gleaned from years of academic research and debate, one thing is for sure: the Strategic Bombing Campaign continues to divide opinion.
Even before the Second World war had ended, and almost non-stop since, debate has raged about whether the Strategic Bombing Campaign was a war-winner or an expensive (in terms of lives lost and resources expended) failure.
“Strategic bombing was not decisive. The question is whether it helped significantly or hardly mattered. The answer is that it made virtually no difference. Even if there had been no strategic bombing campaign at all, the war would have ended in the same way and at about the same time.”
Pape’s view of the Allied Strategic Bombing Offensive is illustrative of the popular criticisms in the decades which followed the war. Both the United States Strategic Bombing Survey (USSBS) (1947) and the later report of the British Bombing Survey Unit (BBSU) concluded that, by and large, the Strategic Bombing campaign had failed to prevent huge increases in production of German aircraft and armaments in 1943 and 1944.
Their research concluded that the main reasons for this were the under mobilization of the German War economy in the early years of the war, inaccuracy of bombing, and the dispersal of German industry in direct response to bombing. The targeting of oil production and transport were considered to be the only areas where the Allies enjoyed any significant success, and even then only in the later stages of the war.
It must be borne in mind that two of the main architects of these reports, economist JK Galbraith in the US and Zuckerman in the UK, were opponents of area bombing. The USSBS was keen to emphasise the “successes” of US precision bombing; the BBSU relied heavily upon the USSBS statistics and findings.
Expanding upon the criticisms identified in both reports, particularly those of Galbraith in the USBSS, and perhaps misinterpreting the findings in Webster and Frankland’s Official History (1961), condemnation of the tactics and achievements of Allied bombing (particularly the area bombing favoured by the British) became, for many years and certainly from the 1960s, de rigeur in academia, and also informed popular opinion.
The work of Overy and Biddle finally began to challenge the accepted historiography in the 1990s and sought to change the way in which the Combined Bomber Offensive is viewed. More recently, historians such as PP O’Brien, Tooze and Harrison have sought to cast new perspectives on the impact of the Offensive, although Malcolm Gladwell’s recent book, The Bomber Mafia, harks back to the criticism of the campaign in earlier decades.
‘COULDN’T HIT A BARN DOOR WITH A BANJO’
Due to technological deficiencies in navigation and accuracy, coupled with lack of numbers of aircraft, early attempts at bombing by the RAF, and from 1942 by the USAAF, proved extremely inaccurate, with significant losses of both aircraft and crew. The Butt report of 1941 found that only a third of RAF aircraft got within 5 miles of their targets.
As the war progressed, improvements in navigational aids (Gee, Oboe, H2S) meant that accuracy was increased but even then the daylight “precision bombing” advocated by the USAAF was more of a hope than a reality, particularly in the face of stiff opposition from Luftwaffe fighters and anti-aircraft ground defences. Overy noted that for the first 3 years of the bombing campaign, there was a “wide gap between expectations and reality”.
Doctrinal differences between the British and Americans resulted in the adoption of a split strategy, with the USAAF undertaking daylight precision bombing of specific industrial and military targets ( the “industrial web” and “bottlenecks” in the supply chain) with large fleets of heavily armed bombers flying in close formation, while the British continued with their controversial policy of area bombing of towns and cities by night, first implemented in Spring 1942 and then pursued with vigour by Air Chief Marshall Arthur Harris for the duration of the war.
The Casablanca Directive of January 1943 confirmed this split approach and set out a generalised targeting strategy for the Allies, with submarine yards then aircraft production heading the list of favoured targets. This strategy was further refined by the Pointblank Directive of 14th June 1943, which identified 19 industries crucial to the German war economy, with fighter production at the top.
I’m going to consider the impact of bombing as measured against the evolving objectives of the Combined Bomber Offensive, and in particular from the time of the implementation Casablanca and Pointblank Directives of 1943 onwards, when US and British joint policy on bombing was crystallised and the full weight of strategic bombing from both the RAF and the USAAF brought to bear upon the German economy.
The issue of the impact of Allied bombing upon civilian morale will be dealt with only insofar as it relates to the workforce and economic production – I could write another 100, 000 words on that topic alone. This piece is NOT going to deal with the morality or alleged illegality of the campaign – that’s a topic for another day. I’m focusing on the strategic /military objectives.
What were the Allies trying to achieve? Let’s look at the broad aims of the Offensive:
1. The damaging and destruction of production facilities (focusing on submarines, aircraft, and armaments) and the “essential” source materials (ball bearings, rubber, oil).
2. The disruption of enemy transport networks, especially rail and waterways.
3. The undermining of civilian morale (and the workforce) by attacking entire towns and cities.
4. The diversion of military resources away from the Eastern front to air defence, and from other “war work”.
I’m going to examine each of these distinct aims individually; in reality they were “distinct in concept more than in practice” due to limitations in technology and bombing accuracy.
THE DAMAGING AND DESTRUCTION OF PRODUCTION
Both the USSBS and BBSU concluded that German war production increased exponentially in 1943 and 1944, before tailing off at the end of that year. German industry produced 3 times as many weapons in 1944 as in 1941; this increase in production has often been presented as evidence of the failure of strategic bombing to achieve its aims, and occasionally as a direct result of the bombing campaign itself.
There is no doubt that German industry was quick to adapt; although the fabric of factory buildings was often severely damaged or destroyed, machine tools and equipment frequently survived. Bombing was inaccurate and was largely unable to inflict sufficient damage to cause production in any one particular industry or of any one particular component to cease.
For example, the 1943 USAAF raids on the ball bearing factories at Schweinfurt destroyed up to 50% of capacity but the USSBS concluded the attacks had “no measurable effect on essential war production”, and in circumstances where the USAAF lost 98 aircraft and crews. Surprisingly, the Allies failed to attack power supplies at all, having overestimated the maintenance and repair capabilities of the German electricity supply network.
Production was often simply dispersed to smaller and more scattered factories; where shortages of components or materials did occur, the gaps were quickly filled by a process of economic osmosis and adaptation, described by the economist Olson in 1962 as “Substitution Theory”. Olson identified that if one part of the economy or industry or even a particular factory was knocked out, the other parts moved to fill the gap in a semi-automatic way.
Factories were concealed by camouflage, and “dummy” sites built to divert the attention of incoming bombers. The range of products being produced was reduced, and production streamlined and standardised to focus on the most essential items. For example, the number of models of vehicles produced was reduced from 55 to 14, and of anti-aircraft guns from 10 to 2. Shortages of manpower were tackled by drawing on labour resources from throughout occupied Europe, through forced labour and the exploitation of inmates from concentration and labour camps.
As Allied Bombing intensified in 1944, some production facilities were moved underground, at the cost of tens of thousands of lives of slave and forced labourers. As the BBSU identified, with increasing experience of air attack, the Germans became more skilled at diverting the effects of air attack onto the civilian economy.
Both the BBSU and the USSBS concluded the German war economy (“The Peace-like War Economy”) had not been fully mobilised up until around 1942, and that there was “spare capacity” . Overy  does not accept that this was a deliberate gamble by a Nazi government banking on a short war, but rather that the level of investment and production were mismatched due to institutional failures to embrace mass production, and military interference; the mass production finally achieved in 1944 came from utilising resources more effectively, even under Allied bombing, and also making increasing use of the supply of female workers.
Bur do these increases in production necessarily mean that the bombing offensive had failed in its primary goal?
As Overy identifies the question is really one of “what might have been”. Under interrogation, Speer stated that but for the bombing campaign, production levels would have been 30 -40% higher. Planned production was much higher than what was actually produced in 1943 and 1944 – for example, the Germans were able to build 35% fewer tanks than they expected in 1944, and 31% fewer aircraft, because of Allied bombing.
Where the Combined Bombing Offensive succeeded was in placing a cap on production, destroying the slack, and preventing industrial increase from rising even higher; it also placed severe restrictions on the achievements of rationalisation implemented by Speer. Dispersal and decentralisation were costly, in terms of investment and the re-organisation of labour and materials, and strained communication and distribution systems.
A rationalised economy with fewer and larger factories was potentially more vulnerable to bombing; dispersal, with its inevitable dependence upon transport, was a clear sign that bombing was handicapping rationalisation, and thereby made transport links a more attractive target. Had synthetic oil production been attacked with intensity at a much earlier date, and prior to May 1944, these effects may have been greater still.
THE DESTRUCTION OF ENEMY TRANSPORT NETWORKS
Both the USSBS and the BBSU identified the bombing campaign against transport (particularly railways and canals) as one of the few successes of the offensive (along with oil); given that Zuckerman, the author of the British report, was one of the architects of the plan to attack the railway system of Occupied France, this is hardly surprising. The BBSU concluded that it was the bombing of the railways which ultimately made the difference, as this cut off supplies and prevented the distribution of existing stock.
Transport, and in particular the railway system, was utterly crucial to German industry, even more so after the process of dispersal began in response to Allied attacks against production. The USSBS identified transport as the weakest link in the German logistical chain, and that “its failure was the immediate cause of the breakdown of the supply system, and consequently was a decisive factor in the breakdown of the German Army”. The US General Ward’s Official History of the campaign found that, “It was clear towards the end of the War that the transportation campaign had paralyzed Germany”, whilst giving rare credit to the RAF for blocking the larger canals in northern Germany.
Pape accepts that while shortages of supply were created by attacks on transportation, strategic bombing was NOT the cause; rather, adopting the findings of US General Omar Bradley, he argues that it was tactical bombing in support of advancing ground forces which destroyed the majority of transport links. However, given that he also concedes that strategic bombing destroyed 20 out of 25 of the railway marshalling yards attacked by the Allies, this argument appears somewhat disingenuous.
Pape also maintains that the bombing of German railways in late 1944 could not have crippled the German economy without the progress of the Soviet army in the East and the Allies in the West, but this is perhaps approaching the issue from an incorrect perspective; strategic attacks on the German transport system meant that attempts to send men, armaments and equipment to wherever they were required, on either front, were thwarted or at least made increasingly difficult, thereby aiding the Allied and Soviet advances. Both strategic AND tactical bombing played a part.
The bombing of transportation targets could naturally only begin to have an enormously disruptive impact on the German war economy once they reached a certain scale, towards late 1944. It was only when the German (and to a lesser extent French) railway systems began to “seize up” in late Autumn 1944 that the real impacts began to be felt. If any criticism can be made of the campaign against transportation, it is that much like the attacks on oil, it should have been conducted on a much larger scale, and at a much earlier stage. It is important to keep in mind that 72% of the bombs dropped on Germany by the Allies fell AFTER 1st July 1944, which is when the main damage to transport targets took place.
Attacks on production could only really succeed when the transportation links which underpinned the supply of raw materials or the distribution of finished goods had been dismantled by bombing. The contribution of RAF Bomber Command to minelaying particularly in the Baltic, and the subsequent disruption of the U-Boat training grounds and enemy merchant shipping bringing much-needed raw materials from Scandinavia, has frequently been overlooked by historians; the BBSU fails to mention it at all.
THE UNDERMINING OF CIVILIAN MORALE
One of the mainstays of the Combined Bomber Offensive was the controversial targeting of German civilian morale; it is perhaps the most difficult of all the aims of the Offensive to measure. Although the Americans did not formally adopt Bomber Command’s policy of “dehousing” (a position which was oddly not reflected in their own policy towards the bombing of Japanese civilians), in reality the limitations of precision bombing, particularly in bad weather in late 1944, meant that in effect the USAAF also participated in “area bombing”, whether they wanted to call it that or not.
The USSBS found that civilian morale had been impacted, but not sufficiently to force capitulation on the totalitarian regime. Pape points out that despite depression, most workers simply continued to work in a routine fashion; as the American survey observed, depressed and discouraged workers were not necessarily unproductive workers.” For many of those whose homes had been destroyed, “going to work” provided them with a sense of purpose, security and routine – for some, it was all they had left. In a totalitarian state, absenteeism was not an option for many.
Bombing attacks on towns and city centres did not translate into the hoped-for extensive worker absenteeism; factories tended to be situated on the outskirts of urban areas, with their workforces living close by rather than in the heart of the cities. The statistics from the Reich Economics Ministry showed that bombing only contributed only to a small increase in lost hours in 1944, although the figures varied hugely from industry to industry and area to area, with absenteeism higher in the western part of the country. Throughout 1944, hours worked in the 12,000 firms surveyed actually increased from 976 million in March to 1063 million in October.
The increasing reliance upon millions of slave and forced labourers, and prisoners of war, also negated this policy – so many of those “employed” in the German war economy simply had no choice; Allied bombing and the policy of “dehousing” was almost an irrelevance in this context as any workers killed or injured in bombing could be replaced.
THE DIVERSION OF RESOURCES
The diversion of military resources away from the Eastern front to air defence, and from other “war work”, was one of the successes of the Combined Bomber Offensive. PP O’Brien argues that taking German war production as a whole, from 1943 onwards the Allies were responsible for “tying down” and destroying a significantly larger share than the Soviet Union. The strategic bombing campaign played a significant part in this.
After the summer of 1943, and the implementation of the Pointblank Directive, the defence of Germany from attacks from the air received the greatest priority, as men, fighter aircraft, anti-aircraft guns and equipment were shifted from every other front in an urgent response to the large scale “round the clock” bombing campaign initiated by the Allies. Critics maintain that the planned diversion of resources failed to draw military forces away from the East; this argument disregards the urgent need for civilian labour within Germany to counter the effects of the bombing campaign, labour which could and was being utilised for “war work” elsewhere.
By January 1944, within 6 months of Pointblank, 54% of all Luftwaffe operational frontline strength was in Germany or occupied Western Europe, with the specific aim of resisting the Bomber Offensive. Milch, the Secretary of State for the Air Ministry, demanded a massive increase in fighter production, observing that Germany itself was now the real “front line”.
Vast amounts of investment, raw materials and manpower were diverted to build fighters and enormous anti-aircraft defences. Over a million personnel were required to man these defences, thereby depriving other parts of the economy of much needed labour, and compelling increased reliance on less efficient forced and slave labour.
Critics of strategic bombing will point to the huge increases in production in 1943 and 1944 as evidence of the failure of the campaign. This narrow perspective misses the wider point. Even though production of aircraft and armaments soared in those years, the additional resources produced were simply swallowed up in the war against the Allies. Attacks on infrastructure, oil and transport meant that it became increasingly difficult for the Germans to deploy the fruits of increased production to wherever they needed to be, whether that was on the Eastern Front, in Italy or indeed in Western Europe, defending German airspace or, from June 1944, attempting to repel the Allied ground invasion.
Such a view is reinforced by O’Brien. Deployment losses were due to stresses placed on logistic and transport systems by Allied air (and sea) power. By 1944, the German war economy could deploy only a small fraction of its actual or potential military capacity into combat.
This massive diversion of resources was not without cost to the Allies. Both sides lost around 40,000 aircraft. Harrison makes the point that aircraft for aircraft, the Allies lost more aircrews (an RAF Halifax or Lancaster would have a crew of 7, a USAAF B17 a crew of 10, while a Luftwaffe fighter would be single-crewed) and more valuable machinery (the cost of a bomber being significantly higher than that of a fighter). However, the Allies were better placed to sustain, absorb, and quickly replace losses of both men and machines. The air war succeeded in forcing Germany to incur major costs to defend it.
THE DESTRUCTION OF THE LUFTWAFFE
By targeting production facilities and resources, the Allies had originally hoped to cripple the Luftwaffe, thereby paving the way for the eventual ground invasion. However, one of the incidental effects of the Strategic Bombing Campaign resulted in the destruction of the Luftwaffe not on the ground, but in the air.
Fighter aircraft were diverted from other fronts; newly produced fighters were thrown straight into the fray, often with inexperienced pilots, with the aim of targeting Allied Bombers on the way to and from the target areas. 1500 Luftwaffe fighter were lost in combat on the Western Front between July and November 1943 alone. While losses of Allied aircraft were high (particularly during the Operation Argument campaign against fighter production in February 1944), American aircraft (and crews) in particular were very easily replaced. German resources were finite; those available to the Americans were many times greater.
The key factor which allowed the Allies to gain command of the air was the introduction of long-range fighter escorts, in particular the P51 Mustang, in 1944. Whereas previous fighter escorts (RAF Spitfires and Hurricanes) could accompany the bomber Squadrons as far as the Low Countries or the peripheries of north western Germany, the bombers were left exposed and vulnerable to fighter attack once their escorts were compelled to turn for home.
Overy makes the point that for too long it was assumed that heavily armed bombers could defend themselves; in reality, they were like unescorted merchant ships at the height of the Battle of the Atlantic. To deliver their deadly cargoes, they needed to be escorted.
The adapted P51s, with the addition of Merlin engines and drop tanks to carry extra fuel, were able to escort their charges right into the heart of Germany and over the target area, drawing Luftwaffe fighters into combat and ultimately destruction. From the Spring of 1944, the escorts took on a more offensive role, flying well ahead of bomber formations, imposing attrition on the enemy air force. The huge increases in German fighter production seen in 1943 and 1944 were to no avail – all of it was either destroyed by, or at the very least diverted to defend against, the Allied bombing campaign.
According to O’Brien, even in 1943, before the introduction of the new long-range fighter escorts, 68.5% of all Luftwaffe combat losses were due to the USAAF and RAF, the remainder to fighting on the Eastern front. For the whole of 1943, he concludes that around 60% of the German war economy was directed against the Allies, a figure which would increase markedly in 1944 and 1945.
Pape argues that the Luftwaffe would still have been destroyed by Allied tactical air power after June 1944 as the ground forces extended their range; this argument does not hold water. By the time of the invasion, the numbers of fighters actually available to the Luftwaffe for deployment on the front (as opposed to the numbers being produced in factories) were falling; only around 300 fighter aircraft were capable of deployment on D-Day. By that time, the Luftwaffe was already in decline, and the number of daylight raids by both USAAF and the RAF began to increase throughout the second half of 1944 as fighter opposition decreased.
The Allied Bombing Offensive did not achieve the much-vaunted “knock-out blow”; it did not bring about the destruction of German morale, nor did it deprive the German war economy of the ability to produce much-needed aircraft and armaments. According to Biddle, the Allies under-estimated the robustness of urban societies and economies in response to bombing but over-estimated the probable efficiency and/or accuracy of that bombing.
The cost to the Allies of prosecuting the bombing war against the German war economy in terms of investment, resources, and the loss of men and machines, was vast. 55,571 RAF men and a similar number of USAAF aircrew lost their lives, with thousands more taken prisoner or injured.
While a number of the traditional criticisms can be partially justified (the failure to target oil and transport at an earlier stage; the failure to attack power generating capabilities at all; the failure to destroy civilian morale), it can be argued that, measured against the aims of the Combined Bomber Offensive, Allied bombing did achieve success in some crucial areas, though perhaps not in the manner originally foreseen.
There can be no doubt that the campaign achieved the creation of a “second front”, diverting aircraft, manpower, armaments, and resources from the war in the East, thereby ultimately aiding the Soviet advance. Although production did increase, the numbers of aircraft, tanks, ordnance and equipment fell far short of that planned for by the German government; production was in effect “capped” by the bombing campaign. Bombing “destroyed the slack”, soaking up increases in production.
The campaign against transportation infrastructure and oil had far reaching impacts in the later stages, and ultimately restricted the ability of the Germans to deploy the fruits of their increased war production to the front.
Perhaps the greatest impact was the unforeseen destruction of the Luftwaffe in combat and the gaining of command of the air, which in turn eventually allowed Allied and Soviet ground forces to advance largely unimpeded by any substantial aerial opposition.
Ultimately, the impact of the Allied bombing campaign on the German war economy should be considered as part of a whole, a significant contribution to the eventual victory, along with ground warfare, and not in isolation. Overy points out that although bombing placed a ceiling on the further expansion of the Germany war economy, production continued to rise until crisis point was reached during the last months of the war, provoked by loss of territory, the failure of the dispersal schemes and the collapse of the repair cycle. Harrison comments that economic warfare and combat went together as “strategic complements”.
Although the campaign was not, as the Allies originally hoped, a war-winning strategy in itself, Pape’s assertion that the strategic bombing campaign made “virtually no difference” determinedly fails to recognise its significant achievements.
If you’ve enjoyed this article, you may be interested in http://www.justcuriousjane.com/bring-up-the-piat and http://www.justcuriousjane.com/lack-of-moral-fibre
My second book, Above Us the Stars: 10 Squadron Bomber Command – The Wireless Operator’s Story (Matador, 2020), explores the Strategic Bombing Campaign from the point of view of one of the crews who took part. You can read more here : http://www.justcuriousjane.com/above-us-the-stars
For more information on the men who took part in the campaign, I thoroughly recommend a visit to the International Bomber Command Centre in Lincoln, UK.
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