Not trying to play devil's advocate or anything but I do feel appalled at the terrible loss of innocent lives in this conflict.
However, I am not sure why you blame the Israelis for that. I say this because the IDF made a pretty good attempt of upholding the Geneva Convention, by dropping leaflets and broadcasting evacuation instructions before military operations would commence.
I don't hear you accusing Hamas which is just as much to blame, if not more, for sending quite a few thousand rockets over the border and using a network of Tunnels to attack nearby Israeli towns.
Even now the Israelis still refuse to negotiate with Hamas, which is understandable, since the organisation has an interesting Constitution of Articles, and Israel is in the process of unilaterally withdrawing from the area.
The only thing you can say is that the response was heavy handed, and that may be true to an extent, but ask yourself this - how would other countries respond?
Unfortunately, it's always the innocent that suffer the most. Hamas, on the other hand, have an existence of privilege. They have the money, the hide outs, the weapons, the medicines, and the caviar, whereas those not in Hamas go day to day and have to dodge the IDF shelling.
Hopefully, Hamas' military capability has been dismantled substantially and we don't hear from them for quite a while otherwise the IDF will come back and I am certain Hamas don't care about that either. It's like the 72 hour humanitarian ceasefire.
They want to draw the IDF into Gaza.