Thunder Bolt
Silly old bat
And hundreds of thousands of Germans and Forced Labourers of all nationalities were killed over the 1942-45 bombing campaigns by the RAF at night and USAAF by day. There is no doubt, however, that strategic bombing (not that the Dams Raid was strictly speaking part of the overall campaign) shortened the war in Europe and saved both Allied and German lives.
The loss of power certainly affected the factories making tanks, and having to repair the dams took resources away from other areas. War is a dirty nasty business.
http://www.bbc.co.uk/news/magazine-22510300