I don't want to be moralistic but it's hard to compare the brutality of the Axis forces and the deaths involved in teh liberation of those countries.
Pls see the diag there :
http://warchronicle.com/numbers/WWII/deaths.htm
8M killed by the allies including 1.6 M civilians causalities (yes far too much)
40M by the Axis regimes including 25.6M of civilians ! (and those countries did not really have strategic bomber forces)
Obviously you don't kill 40M of ppl just by signing your name on an order form (at that time there was no nuke to be feared). Millions of others had to be committed in the blood bath.