With his growing interest in an attack on the Soviet Union, Hitler, on 19 July 1940, offered peace, with Britain to retain her empire in return for her acceptance of Germany’s dominance of the Continent. Influential politicians, particularly the Foreign Secretary, Lord Halifax, who had come close to succeeding Chamberlain, felt that such negotiations were desirable, while David Lloyd George, Prime Minister in 1916–1922, thought he might be able to succeed Churchill and settle with Hitler. Churchill, however, was determined not to negotiate with Hitler, and his views prevailed.
Moreover, in the Battle of Britain of 1940, the German air assault was defeated. This was a key episode both in British military history and in the history of air power. It was the first major check experienced by the Germans, and one that was critical to the survival of Britain as an independent state, for the air attack was designed to prepare the way for Operation Sealion, the planned invasion, particularly by driving British warships from the Channel. British victory reflected both the deficiencies of the numerically superior German air force, and the capabilities and fighting quality of its numerically inferior British opponents. Radar also played an important role within an integrated air defense system. Initial German attacks on the RAF and its airfields, in what was an air superiority campaign, designed to force the British to commit their fighters and then to destroy them, inflicted heavy blows on the British, especially on pilot numbers. By early September, Fighter Command, under remorseless pressure by larger forces, seemed close to defeat. However, fighting over Britain, the RAF benefited from the support provided by the ground control organization and could more often recover any pilots who survived being shot down. Furthermore, RAF fighting quality, which had been underestimated by the German planners, was seen in the heavy losses inflicted on the Germans, and the Germans did not appreciate the extent to which the RAF was under pressure.
Once the Germans switched in early September 1940 to bomb London and other cities (the Blitz), a strategy designed to put the German air force center-stage by bombing Britain into submission, the pressure on the RAF diminished. German bombers operating near the edge of fighter escort range provided a vulnerable target, which led the Germans to switch to night attack. There is controversy over losses, but one reasonable assessment is that between 10 July and 31 October, the Germans lost 1,733 aircraft in the Battle of Britain, the British 915. Although German deficiencies played an important role in their failure, British fighting quality, determination, and fortitude were crucial in making these deficiencies manifest, and thus in gaining an important defensive victory.
Nevertheless, the strain on the British people of coping with the Blitz was heavy. The range and repetition of the bombing increased the uncertainty and tension it imposed. For example, the city of Swansea was bombed 44 times in 1940–1943, with 1,238 people killed or wounded, over 7,000 made homeless, and the town center destroyed. Nevertheless, on the whole, morale remained high, and fortitude in the face of the attack became a key aspect of national identity. The real and symbolic aspect of the assault on British civil society accentuated the sense of the entire society being under attack, and this had considerable effect both at the time and for postwar Britain. Churchill told the House of Commons on 21 November 1940, ‘‘The War Damage (Compensation) Bill. . .will give effect to the feeling that there must be equality of risk and equality of treatment in respect of the damage done by fire of the enemy.’’
On 17 September 1940, Operation Sealion had been formally postponed. Irrespective of the serious problems that would have faced any invasion, not least insufficient German naval resources and preparation and the strength of the British navy, it could not be allowed to go ahead without air superiority. Furthermore, the British navy was able to defeat the attack of German surface raiders on British communication links and to limit those by submarines, and the empire provided key assistance, ensuring that, unlike against Napoleon, Britain did not fight alone. Thanks in particular to the support of imperial forces, the British were able to launch a peripheral strategy designed to protect vulnerable interests and to hit at opponents in an indirect fashion.