Remembering the blitz: was it an avoidable tragedy?

From the Guardian

"Just after 4.30pm on Saturday, 7 September 1940, 364 German bombers and 515 fighters flew across the Channel and followed the Thames estuary to London, using the fires caused by their bombs as markers. They came for a further 75 consecutive nights (except for one that was too cloudy for the bombers to operate). The blitz would last until 16 May 1941 – when most of the Luftwaffe was reassigned to the invasion of Russia. In 1940, 13,000 people were killed in London alone. Attacks on other major cities throughout the UK began on 15 October 1940, with the centre of Coventry being destroyed on the night of 14/15 November."