But how serious will the retaliation be? That is the question that has yet to be answered. There have been at least two dozen air strikes in Gaza so far today, and there are unconfirmed reports coming out of the territory that other senior Hamas officials have been targeted.

Will there be a ground incursion? Israeli Home Defense Minister Avi Dichter seemed to call for one when he said Tuesday: "There is no precedent in history of destroying terror by air power alone. It hasn't happened and it won't happen.