If this arithmatic were the result of Hezbollah's moral restraint, then the respective casualties would mean something. Given that the only reason that Israeli casualties are that low because Israel is prepared for such attacks, and Hezbollah's weaponry is less effective at killing civilians than they'd like, we are once again confusing things which are physically equivalent with those that are morally equivalent. By that logic if the Germans had succeeded in killing only a fraction of the number of German civilians that England had succeded in killing , despite the Germans's best efforts to kill many more, the German's would have been the morally superior actor in that conflict.
I don't know about that... the 18->600 strikes me as a disproportionate retaliation, which really has no parallel to WWII. A more apt parallel would be WWI where the assassination of one man escalated into the deaths of millions.