The people to blame are the people who give the orders, not the ones who follow them. Trashing the guy’s relatives’ houses is a waste of time. Trashing the Palestinian leadership might be much more effective. If you kill the general who orders the private to murder civilians, he’ll stop giving such orders. It is unlikely the private is someone who would likely kill people left to his own devices (unlike a regular “perp”). It is dubious if it is wise to execute enemy prisoners as they were willing to die for the cause when the signed up (no deterrent effect), and they make good hostages.

To compare to a similar situation: executing privates who enjoyed following orders to kill Jews during WWII has not had any effect on preventing a renewal of Naziism. Conquering Germany, killing its leaders, and forcing all Germans to believe they had nothing to do with the government they elected and supported, etc. – has in fact rendered Germany quite harmless from out perspective (and note that even if they were allowed to participate in politics, the Nazis have little support in Germany).