Some of the English pilots involved regard the fire-bombing of Germany as a war crime. Indeed, one of the reasons it wasn't a war crime is because it no-one thought a country would bomb civilians and so "don't target civilians" didn't get written into any treaties.
The change in attitude throughout the war, starting from a position of "do not bomb civilians" and ending with "fire bomb civilian populations to kill as many civilians as possible, in a probably horrible way" is covered nicely in Max Hastings' book "Bomber Command".
English Bomber Command suffered heavy losses. About 55,000 aircrew died, of a total about about 125,000 men. (That's around a 44% death rate, which is uncomfortably close to a coin-toss.)
The change in attitude throughout the war, starting from a position of "do not bomb civilians" and ending with "fire bomb civilian populations to kill as many civilians as possible, in a probably horrible way" is covered nicely in Max Hastings' book "Bomber Command".
http://www.amazon.co.uk/Bomber-Command-Pan-Military-Classics...
http://www.amazon.com/Bomber-Command-A-Touchstone-book/dp/06...
(Why are US book covers so weird?!)
Wikipedia has a tl;dr https://en.wikipedia.org/wiki/RAF_Bomber_Command
English Bomber Command suffered heavy losses. About 55,000 aircrew died, of a total about about 125,000 men. (That's around a 44% death rate, which is uncomfortably close to a coin-toss.)