The official Israeli explanation, as of last night, anyway, was that they were attempting to kill some Hamas people on a motorcycle that was passing by the school. So they were trying to hit something moving in the road nearby, it was not a stray round or something that struck where it did by gross mistake. I have pointed out before that the standard an attacker must meet when attacking a legitimate military target, if doing so could endanger non-combatants, is that the direct military benefit gained by neutralizing that target must be so great as to outweigh the risk of harm to non-combatants. I understand people may view that balance differently, and that reasonable people of sound mind and good heart might come to different conclusions as to where it rests in specific instances, but as someone willing to give latitude to claims of military necessity, I assure you that there is no way in Hell a reasonable argument can be made for the proposition that the direct military benefit of killing a couple of people on a motorcycle, however militant and combatant they may be, is or can be sufficiently great as to outweigh the risk of harm to non-combatants inherent in trying to land artillery in the street alongside a facility known to be sheltering several thousand non-combatants.