To start with, Harris, Portal and even Churchill objected to the American insistence on daylight attacks, largely because they thought the whole policy was doomed. It was one thing to hit a practice target in the clear blue skies of California, but a different thing altogether to find a specific building in the centre of a German city, especially when that city might be shrouded in the thick cloud of a European winter, and defended by both Luftwaffe fighters and walls of predictive flak. ¹⁶The Americans refused to be swayed, and it took them until the second half of 1943 to come to the painful realization that, in the absence of a long-range fighter escort, their terrible losses in the skies over Germany would be too heavy to bear.

But all that was in the future. For now the policy of daylight bombing seemed to be successful, largely because the Americans confined their fledgling efforts to targets in western France or the Low Countries, where they could still be accompanied by fighters. By the end of 1942 the Americans had flown more than 1,500 sorties in twenty-seven operations (missions), and lost only thirty-four aircraft – a loss rate of just two per cent. American optimism was so high that in August 1942 Ira Eaker confidently predicted that he and Butch Harris together would be able ‘completely to dislocate German industry and commerce and to remove from the enemy the means for waging successful warfare’ as early as the middle of 1943. ¹⁷When the two leaders were finally to join forces in the bombing of Hamburg, his prediction would almost come true.

* * *

Right from the beginning the British and American air forces had worked closely together, and their co-operation was formally sealed when British and American military and political leaders met in Casablanca in January 1943 to plan a combined air offensive against Germany. Since the Allies were not yet strong enough to attempt an invasion of mainland Europe it was decided that the only way to carry the fight to the Axis powers was to increase the bombing campaign. Indeed, if the Allies were ever to attempt an invasion, it was essential that they first achieved air supremacy over the Germans.

To this end, the Combined Chiefs of Staff issued a directive to Air Marshal Harris and General Eaker, ordering them to begin demolishing a range of German targets: submarine yards and bases, aircraft production, ball-bearing factories, oil and rubber plants, and military-transport systems. They were also required to undermine German morale, as the preamble to the directive made clear: ‘Your primary aim will be 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…’ ¹⁸The plan was to subject Germany to a round-the-clock bombing campaign on a vast scale. RAF Bomber Command would continue their campaign against the cities by night, while the US Eighth Army Air Force would attack specific military targets by day.

The coming year would be very different from anything that had gone before. Attacks would be bigger, more widespread, and they would be repeated again and again until the destruction was total. Over the next six months the Americans built up their air force from eighty or so operating planes to a force of well over three hundred, and accumulated vital combat experience over targets in northern Europe. The British, meanwhile, began a relentless offensive against the industrial cities of the Ruhr. In March they hit the Krupps armament factory in Essen, causing severe damage to buildings and machinery. In May they devastated Dortmund and Wuppertal in quick succession, especially the latter, where a miniature firestorm consumed most of the city centre. In June they attacked Düsseldorf, starting fires that raged over forty square kilometres – twenty military installations were hit, seventy-seven companies put out of business, and 140,000 people were made homeless.

Germans all over the country noticed the increasing intensity of the bombing, and gossip flew from one city to the next. Wild estimates of the death tolls circulated: in Dortmund, they said, fifteen thousand people had been killed (the figure was actually around six hundred), in Düsseldorf seventeen thousand (in reality it was twelve hundred) and in Wuppertal twenty-seven thousand (actually 3,400). ¹⁹Worse than the numbers being touted were rumours about how people had died. Tales were told of victims being turned into living torches by the phosphorus bombs, or becoming stuck in the melted asphalt of the roads. Such rumours certainly reached Hamburg, but few who lived there truly believed that the same fate lay in store for their city. When British reconnaissance planes dropped leaflets claiming that Hamburg would be next, no one heeded them: even those Germans who thought the Nazis were doomed believed that Hamburg would be left largely intact, because the British and Americans would need the town and its harbour later on. ²⁰Besides, propaganda leaflets had been dropped throughout the war, and few people paid much attention to them.

But Hamburg would indeed be next. Even while Dortmund and Düsseldorf were still reeling from their attacks, Harris issued an operations order in which he stated his intention ‘to destroy Hamburg’: ‘The “Battle of Hamburg” cannot be won in a single night. It is estimated that at least 10,000 tons of bombs will have to be dropped to complete the process of elimination. To achieve the maximum effect of air bombardment this city should be subjected to sustained attack.’ Moreover, having learned that fire was the best weapon, Harris ordered that most of the bombers should carry ‘maximum economic incendiary loads’ to saturate the fire services of the city. ²¹

Harris expressed the hope that the Americans would join in with the bombing of Hamburg, but it was not up to him to make that decision. Until now the USAAF had never bombed a target that the British had bombed the previous night – it was deemed too dangerous – and ‘round-the-clock bombing’ had been merely a theory, not a reality. But the Americans also had their eye on Hamburg. The city contained many targets that they considered high priority, including aircraft-parts factories and submarine builders. US planes had tried to attack the city at the end of June, but had been forced back by heavy cloud. Now, weather permitting, they would be all too happy to join the RAF, and when General Eaker issued the order to attack the Blohm & Voss shipyards on the banks of the Elbe, Hamburg’s fate was sealed.

It must be said that not everyone on the Allied side was happy about this new target. Shortly before the attack took place Sir Henry Tizard, the brilliant academic who was responsible for creating the British radar network, wrote to the Prime Minister expressing his misgivings about the proposed series of raids. He was an outspoken critic of many aspects of British bombing policy, and doubted that the war could ever be won by bombing alone. He was particularly unhappy about the prospect of destroying Hamburg, a city that he believed was essential to keep intact so that it could be used to administer Germany after the invasion: ‘Hamburg is anti-Russian, anti-Prussian and anti-Nazi. It may well be soon, if not already, anti-war. Apart from submarine construction and shipping, generally it is not industrially important. It is a centre of commerce rather than of production. It is a very important port and might therefore be much more useful to us alive than dead.’ ²²

Churchill did not agree, and neither did the Chief of Air Staff. In a strongly worded rebuttal, Sir Charles Portal pointed to the numerous industrial, chemical, transportation and engineering targets within the port. ‘It seems abundantly clear that Hamburg is much more than a dormant centre of peace-time commerce,’ he said, ‘and, if so, I certainly do not think we should refrain from bombing it.’ ²³