Bombers carry out three principal missions: close air support (attacks on enemy forces engaged in combat against ground forces), air interdiction (attacks on infrastructure, supplies, and forces moving towards the battlefield), and strategic bombing (attacks on the enemy’s production system). In the First World War, bombers almost exclusively focused on the first two of these missions. The Second World War, by contrast, was the first major conflict in which strategic bombing formed an integral part of overall strategy.
Giulio Douhet (1869-1930), an Italian general, was one of the most influential proponents of strategic bombing, arguing that airpower could annihilate the production capability of the enemy by itself and cause them to surrender. Military decision makers in London quickly seized on his ideas in 1939, hoping to knock Germany out of the war before it truly began.
In practice, it became instantly clear they had vastly overestimated bombers’ accuracy and their ability to penetrate enemy defences. During a probing attack on 4 September 1939, ten RAF bombers attacked the German fleet at Wilhelmshaven, losing seven of their own for no significantly damaging hits. America’s Norden bombsight, which promised to allow crews to land half of their bombs within a radius of twenty-three metres from their targets during trials, only allowed them to land half within three hundred and seventy in actual combat conditions. Douhet’s theories seemed inapplicable to real warfare.
Nonetheless, despite being forced into suboptimal altitudes and times of day by flak (anti-aircraft fire) and fighters, Allied bombers still managed to inflict critical damage on the build-up of German industry as the war progressed. In an effort to ‘de-house’ German workers, a third of the houses in Hamburg were destroyed from late July to early August 1943. The amount of resources required to re-settle the city’s inhabitants so production could resume bordered on catastrophic. Goebbels, one of Hitler’s closest confidants, wrote in his diary: “A city of a million inhabitants has been destroyed in a manner unparalleled in history. We are faced with problems that are almost impossible of solution…Kaufmann [the local governor] spoke of some 800,000 homeless people who are wandering up and down the streets not knowing what to do.”
However, the policy’s ultimate goal, the collapse of German morale and a revolution against the Nazi regime, was never achieved. British policymakers had embarked on this misadventure on the basis of a survey of the cities of Hull and Birmingham after the Blitz, which they misconstrued as concluding that the effect of de-housing on morale was even greater than that of losing loved ones. In actual fact, it did not stop either country fighting till the bitter end, as the German war effort was only truly stopped by a two-pronged land invasion.
More promisingly, the United States Strategic Bombing Survey (USSBS), using German documents made available after the war, identified the attack on the Nazis’ oil supply as one of the greatest successes of the campaign. Albert Speer, Minister of German War Production, reported “losses of aviation gasoline up to 90 percent” on June 22, 1944. He later wrote in his memoir that the attacks on the oil industry “meant the end of German armaments production.” Crucially, he noted that “the chemical plants had proved to be extremely sensitive to bombing” and that “even optimistic forecasts could not envisage production being resumed for weeks” after an individual attack. After the main source of fuel for the Axis, the Romanian oil fields, was hit on May 28, “production was actually reduced by half”.
This had devastating consequences for the Wehrmacht’s ability to operate its tanks and aircraft. During Germany’s final large offensive at the Battle of the Bulge in the winter of 1944, into which they threw the very best of their remaining armed forces, German tanks advanced a mere fifty miles before the fuel situation became untenable. The German high command had counted on the capture of Allied fuel depots intact. Their destruction doomed the campaign’s ultimate objective of reaching the Channel ports and repeating the successful encirclement of the Battle of France of 1940.
However, not all Allied commanders were entirely complementary of this strategy. Indeed, Arthur ‘Bomber’ Harris – commander of RAF Bomber Command, was rather disparaging of the oil campaign. Whilst he noted that it had been “a complete success”, he argued that it had been launched on the basis of flimsy intelligence: “what the Allied strategists did was to bet on an outsider, and it happened to win the race”.
Certainly, the inadequacy of Allied intelligence-gathering led to the adoption of profoundly inefficient bombing strategies. For example, few attacks were made against the German power network, even though “the destruction of a total of 95 plants of 50,000 kW or larger would have eliminated over one-half of the entire generating capacity of the country” according to the USSBS. A raid on August 17, 1943 on plants in Schweinfurt producing ball bearings (at that time a limiting factor in German engine production) reduced national output by 38 percent. On October 14, national output was reduced to a third of ‘intact’ levels. These staggering successes were achieved despite the fact that the Allies, not appreciating the criticality of the ball bearing industry, had diverted forty percent of their aircraft in the area towards an attack on the airframe industry.
Catastrophe for Germany was only averted by the Allies’ decision to cease ball bearing attacks on the assumption that Nazi administration was efficient enough, in the words of Sir Arthur Harris, to “have long since made every possible effort to decentralize the manufacture of so vital a product” – an overestimation of Speer’s success in shielding key industries from Allied bombing raids, such that by August 1944 decentralisation of ball bearing production was only just starting.
Speer’s nightmare, the enemy realizing “that he could paralyze the production of thousands of armaments plants merely by destroying five or six relatively small targets”, therefore came true far later than it should have. The example of WW2 strategic bombing provides us with yet more evidence that the maxim of the great military theorist Clausewitz – “pursue one great decisive aim with force and determination” – is a universal and fundamental principle of war.
von Clausewitz, C., 1812. Principles of War, Chapter II. https://www.clausewitz.com/mobile/principlesofwar.htm#II
Shirer, W.L, 1960. The Rise and Fall of the Third Reich, Chapter 28. Simon & Schuster.
Speer, A., 1970. Inside the Third Reich, Chapter 24. Orion Books.