not at all....ww2 was not a one-sided offensive.
Yes, but relative weakness does not mean moral superiority. If it did, then the Nazis would have been the "wrong" side in 1939 but the "right" side in 1945. Every wanted criminal is fighting against a law enforcement agency much more powerful than himself. Does this mean escaped murderers are morally superior to the police because it's a "one-sided offensive"?
In any rate if things have been reversed -- if the Israeli offensive had suffered heavy casualties -- it isn't as if the same people blaming Israel for the offensive being "one sided" would side with Israel for being "balanced". They would be doing victory laps about how this proves the Palestinians' bravery and willingness to fight against the evil zionists -- even, indeed especially, if the Israelies were to suffer much heavier casualties than Hamas. All concerns of a "one-sided conflict" would, of course, be dismissed so long as more Jews than Palestinians are killed.
Since Israel would be condemned anyway, it's far better for it to be condemned for the struggle being "one sided".