The IDF operation in Gaza - Defensive Shield, or in its better, Hebrew version, Amud Anan - has been on for about 70 hours. According to the twitter feed of the IDF, as of this morning more than 500 targets had been hit from the air in Gaza, many of them underground storage installations of weapons.
We don't know how many people in Gaza have been killed so far. The highest number I've seen is 18. Of them, how many are civilians? We don't know that, either. Some of them. The death of any non-combatant is always tragic (The deaths of terrorists is tragic for their families, but they made the choice to be terrorists and their possible death was part of that choice).
Nor do we know what lies in the future. It's sadly possible that an hour from now, or a day, or next week, an Israeli piece of ordinance will kill a large number of Palestinian civilians. This happens all too often in wartime. Yet even if that happens, the fact of the operation's first three day will be unchanged. Israel attacked hundreds of military installations in the middle of densely populated parts of Gaza because that's where Hamas was positioning them; Israel knew precisely where they are even when they were carefully hidden underground; and Israel managed to destroy them with the loss of perhaps ten Palestinian civilians, perhaps fewer.
All of which goes to disprove the entire narrative about the blood-thirsty Israelis callously (gleefully) slaughtering innocent Palestinians etc. etc. etc.