The city of Cologne in March 1945 after several bombing raids. National Defence Image Library, PL 42542.

Between the two world wars, advances in aeronautics were such that a theory was born, claiming that, with aircraft flying increasingly faster and higher, no country could survive systematic high-explosive and incendiary bomb strikes. Pre-emptive, offensive bombing, that would crush the enemy before it can engage in such action, was therefore deemed to be the only way to escape utter destruction. The doctrine of strategic bombing resulted from that theory.

In June 1940, with its European allies fallen to the Third Reich, Great Britain had lost access for a land attack against Germany. Air strikes were then the only offensive weapon available against the Nazis. In July 1941, British chiefs of staff stated: “We must destroy the foundations upon which the war machine rests, the economy which feeds it, the morale which sustains it, the supplies which nourish it, and the hopes of victory which inspire it.”
Quoted in Greenhous et al., p. 551

At that time, the British doctrine still favoured precision bombing against military objectives: factories producing military equipment, oil and fuel refineries, naval and air bases, etc. Most air raids targeted the Ruhr, Germany’s industrial heart. But results were disappointing: navigators could not locate their targets in the dark of the night and few bombs fell within three miles (4.8 km) of their intended target. The destruction effect was much less than anticipated.

Damages resulting from bombing in a residential area of Cologne. National Defence Image Library, PL 42543.

To obviate the inefficiency of precision bombing, area bombing was experimented. This new approach stated that air raids should cause material damage to any structure in the target’s vicinity. Area bombing meant casualties among civilians, who would be killed, wounded or left homeless, thus impacting on both the population’s morale and on the enemy’s production capacity. Sir Arthur Harris, Bomber Command’s commanding officer since February 1942, became the main proponent of that doctrine that he submitted to the Chiefs of Staff and to the British Government. Let us not forget that Britain herself was being submitted since 1940 to “terror bombings”, i.e., night raids targeting civilian as well as military objectives. Facing a desperate situation – Nazi military successes in Western and Eastern Europe, devastating attacks against maritime traffic, uninterrupted bombing raids against Britain – the British Government considered that attacking Germany’s civilian population was justified.

In 1941 and 1942, area bombings did not yield the expected results. Actually, bombing raids were rather ineffective, while resulting in a high number of casualties among Allied air crews, the main causes being the aircraft insufficient performances and the outstanding German air defence system that bombers had to defeat.

Mass Bombings

Railway installations destroyed in bombing raids in Trappes, near Paris. The photograph is dated September 9th, 1944. National Defence Image Library, PL 32254.

In order to break through German air defences and maximize destructive power, Air Vice-Marshal Sir Arthur Harris organized the first mass bombing operation, code-named Millenium. In the night of May 30th, 1942, 1,096 bombers flew in successive waves over Cologne. The raid, which lasted only two hours and a half, caused destruction on an unprecedented scale: 600 acres almost totally laid waste, 3,300 buildings destroyed, 2,500 fires started, some 500 people killed. For Harris, this demonstrated the power of Bomber Command as a strategic weapon, one that could defeat the Third Reich all by itself.

That raid set the pattern for bomber warfare as it would be practiced until 1945. The Casablanca Directive, under the joint responsibility of U.S. President Franklin D. Roosevelt and of British Prime Minister Winston Churchill, sanctioned by U.S. and British chiefs of staff on January 21st, 1943, assigned the following objective to bombing operations: “the progressive destruction and dislocation of the German military, industrial and economic system and the undermining of the morale of the German people to a point where their capacity for armed resistance is fatally weakened”
Quoted in Greenhous et al., p. 657

While the Eighth U.S. Air Force attacked by day, Sir Arthur Harris’ Bomber Command engaged in night operations against the very heart of the German Reich, its capital, its major industrial centres, its civilian population. Cities are practically wiped out: Cologne, Essen, Dortmund, Düsseldorf, Hanover, Mannheim...

The Vokel (Netherlands) airfield pitted with craters after a 6 Group attack, September 3rd, 1944. National Defence Image Library, PL 32218.

In the night of October, 22nd to 23rd, 1943, Kassel was bombed: 155 industrial sites were damaged, including three Henschel factories, producing locomotives, tanks and guns. Over half the city was destroyed: 8,500 people died, 100,000 were left homeless. On the basis of data provided by the Air Ministry, British press highlighted damages inflicted to the war industry but downplayed the impact on the civilian population, a perspective that infuriated Harris, who saw it as a misrepresentation of truth. He believed that Bomber Command’s prime objective had to be stated unequivocally.

“That aim is the destruction of German cities, the killing of German workers and the disruption of civilised community life throughout Germany. It should be emphasised that the destruction of houses, public utilities, transport and lives; the creation of a refugee problem on an unprecedented scale; and the breakdown of morale both at home and at the battle fronts by fear of extended and intensified bombing are accepted and intended aims of our bombing policy, they are not by-products of attempts to hit factories.”
Sir Arthur Harris, 25 October 1943, quoted in Greenhous et al., p. 725.

In Hamburg, during the night of July 27th to 28th, the heat and strong winds spread the blazes started by the air raids, turning the downtown core into a fiery inferno in which 41,800 people lost their lives. Between November 18th, 1943, and March 31st, 1944, Allied bombers pounded Berlin; despite massive destruction of industrial facilities and administrative buildings, despite heavy casualties in the civilian population, Germany stood firm and morale did not collapse, as expected.

Daytime attack against Hanover, March 25th, 1945. National Defence Image Library, PL 144266.

In April 1944, Bomber Command was placed under the control of Supreme Headquarters, Allied Expeditionary Forces (SHEAF). In the following months, bombing raids targeted essentially the transportation infrastructure – rail yards, railway lines, trains – in France, Belgium, and the Netherlands, in order to cut off the Normandy battleground from Germany. Strategy reverted to precision bombing in order to spare the friendly civilian population. In Germany, however, area bombing and the destruction of urban centres in the north and west of the country were carried on until 1945.

In Sir Arthur Harris’ opinion, strategic bombing was, as an offensive operation, as important as the opening of a new front. Until D-Day, he was convinced that bombings, if they were destructive enough, could force Germany into submission without the Allied casualties that were bound to result from a massive landing operation in Continental Europe. After D-Day, uninterrupted waves of hundreds of bombers, carrying thousands of bombs, kept on pounding German cities every night, in an attempt to bring about the collapse of the Third Reich.

In retrospect, we know that the Allies won through a combination of ground, naval and air operations. It is only after V-E Day, that some light could be shed on the actual effects of bombings. Despite the massive destruction suffered by Germany, the morale of the civilian population remained quite high until the very last few months. In addition, if the war industry was indeed slowed down by bombings, it was never brought to a complete halt; being very decentralized, it could escape raids that focused mostly on urban centres.