Editing The Blitz (section)

===Change in strategy===
Regardless of the ability of the {{lang|de|Luftwaffe}} to win air superiority, Hitler was frustrated by its slow advance. With no sign of the RAF weakening, and the {{lang|de|Luftflotten}} suffering many losses, OKL was keen for a change in strategy. To reduce losses further, strategy changed to prefer night raids, darkness offering the bombers greater protection.<ref>Ray 1996, p. 101.</ref>{{efn|Williamson Murray's ''Strategy for Defeat'' indicated a serious decline in operational readiness. In mid-September, Bf&nbsp;109 units possessed only 67 percent of crews against authorised aircraft, Bf&nbsp;110 units just 46 percent, and bomber units 59 percent.{{sfn|Murray|1983|p=52}}}}

It was decided to focus on bombing Britain's industrial cities, in daylight, to begin with. The main focus was London. The first major raid took place on 7 September. On 15 September, on a date known as Battle of Britain Day, a large-scale raid was launched in daylight, but suffered significant loss without any lasting gain. Although there were a few large air battles fought in daylight, later in the month and into October, the {{lang|de|Luftwaffe}} switched its main effort to night attacks,  official policy starting 7 October. The air campaign against London and other British cities soon got underway.<ref name="Overy 1980, p. 35."/>

However, the {{lang|de|Luftwaffe}} faced limitations. Its aircraft—[[Dornier Do 17]], [[Junkers Ju 88]], and [[Heinkel He 111]]s—were capable of carrying out strategic missions<ref>Corum 1997, p. 282.</ref> but the damage they were capable of doing was limited due to their small bomb loads.<ref name="Overy 1980, p. 35.">Overy 1980, p. 35.</ref> The {{lang|de|Luftwaffe}}'s decision, in the interwar period, to concentrate on [[medium bomber]]s can be attributed to several reasons: 
* Hitler did not intend or foresee a war with Britain in 1939.
* The OKL believed a medium bomber could carry out strategic missions just as well as a [[heavy bomber]] force.
* Germany did not possess the resources, nor technical ability, to produce four-engined bombers, before the war.<ref>Murray 1983, pp. 10–11.</ref>

Although it had equipment capable of doing serious damage, the {{lang|de|Luftwaffe}} also had an unclear strategy, and poor intelligence. The OKL had not been informed that Britain was to be considered a potential opponent, until early 1938; it had too little time to gather reliable intelligence on Britain's industries. 

Moreover, the OKL could not settle on an appropriate strategy. German planners had to decide whether the Luftwaffe should deliver the weight of its attacks against a specific segment of British industry (such as aircraft factories), or against a system of interrelated industries (such as Britain's import and distribution network --  or even in a blow aimed at breaking the morale of the British population.<ref>Murray 1983, p. 54; McKee 1989, p. 255.</ref> The {{lang|de|Luftwaffe}}'s strategy became increasingly aimless, over the winter of 1940–1941.<ref>Overy 1980, pp. 34, 37.</ref> Disputes among OKL staff revolved more around tactics, than strategy.<ref>Hooton 1997, p. 38; Hooton 2010, p. 90.</ref> This lack of clarity condemned the offensive over Britain to failure, well before it had begun.<ref>Bungay 2000, p. 379.</ref>

In an operational capacity, limitations in weapons technology, and quick British reactions, were making it more difficult to achieve strategic effect. Attacking ports, shipping and imports, as well as disrupting rail traffic in the surrounding areas (especially the distribution of coal, an important fuel in all industrial economies of the Second World War) would net a positive result. However, the use of [[delayed-action bomb]]s, while initially very effective, gradually had less impact, partly because they failed to detonate.{{efn|This was caused by moisture ruining the electrical [[fuze]]s. German sources estimated 5–10 percent of bombs failed to explode; the British put the figure at 20 percent.{{sfn|Hooton|2010|p=84}}}} The British had anticipated the change in strategy and dispersed its production facilities, making them less vulnerable to a concentrated attack. Regional commissioners were given plenipotentiary powers to restore communications, and to organise the distribution of supplies to keep the war economy moving.{{sfn|Hooton|2010|p=84}}