I find this whole proportionality meme strange.
My take on Israeli strategy, now and particularly in 06 and 08, is that it's collective punishment. They can't really fight an enemy hiding among its populace, not fight them properly. So they take out what military personnel and facilities they can, while sending a message that says, "If you attack our cities we will blow the absolute shit out of your infrastructure and do as much damage as we can until daddy tells us to stop."
As a strategy, I think it's basically evil. But I also think it's what pretty much every state does if the guys next door are shooting rockets at its major cities - irrespective of casualties. The reality is that politicians are accountable to their people, and if retaliation is a military option people won't accept anything less. It's what Russia did in Chechyna when terrorists hit Moscow, it's what Sri Lanka did with the Tigers. America had a city attacked 12 years ago and they're still bombing several entire countries.
It's only with Israel, and maybe America, that we get this level of coverage, pictures of kids with missing limbs on football message-boards, etc. Which is for the best I suppose, if it happens to reduce casualties in this one conflict.