The virtue of “proportional response” (as the president in the movie asks so eloquently) is to deter further acts of violence without creating an escalation in the violence. In the case of Israel and the Arab population living in Israel and the Palestinian Authority the idea of proportional doesn’t exist. That is because of the Muslim concept of “temporary peace”. The Muslims have pledged to kill all Jews and wipe Israel off the map. They send civilians, men, women and children to stab, run over and blow up Israeli men women and children. They encourage this kind of aggression. They celebrate it. Their history has taught that they will not live in peace with infidels. The only time Muslims live in peace with infidels (according to their beliefs) is when the infidels are more powerful than they, and there is no choice.
Back to the original question. It’s not too complicated. What is the proportional response to violence from people who would be happy to destroy the Jewish Nation and wipe Israel off the map if they only could?