One moral narcissist with whom I've regularly sparred before had a simple answer to the question of what the Palestinian national movement (PNM) wants and what it would do if Israel were to withdraw to the armistice line as "international law" demands. His response was that he did not know what the PNM wants, but that if the PNM were to use its newfound sovereignty over the territories to launch a war to take all of Israel, that Israel would be justified in responding in kind and waging defensive war against Palestine. This is a very facile argument and thus very dangerous because the peaceniks would be inclined to latch on to it for the same reasons that people latch on to Donald Trump's call to bar immigration by Muslims. To defuse this threat, it would help to explain what would be a realistic possibility of the PNM's response to Israeli withdrawal and why even with Israel being "free" to respond, withdrawal would be imprudent without some reason to believe that that would not be the PNM's course of action.
When the moral narcissists say that Israel would be free to defend itself against a Palestine waging war to take over the rest of the land, they are probably thinking of a conventional invasion. One thing we can be certain of is that there will be no conventional invasion because the PNM knows that they have zero chance of prevailing in such a conflict. Rather, what is more likely is that the first action of the government of the new State of Palestine would be to amass an arsenal of rockets and mortars to be stored in Tulkarem, Qalqilya, Ramallah and Abu Dis. With full control over the Jordan Valley and the roads from the Valley inland, this would not be difficult. Once they accumulate a sufficient arsenal, they will look for a pretext to use this arsenal in a war of terror. The mortars would be launched from Qalqilya against Kefar Sava and from Abu Dis against western Jerusalem while the rockets would come from all the list population centers listed against the Jerusalem-Tel Aviv-Netanya corridor.
This is where the moral narcissists' claim that Israel would be free to defend herself will break down. Not only will the mortar/rocket attacks ensue from the aforementioned places, we can be certain the ordnance will be stored in and launched from schools, hospitals and apartment complexes. This would leave Israel the choice of turning the other cheek as mortars and rockets rain down on the core of her population or counterattacking against the schools, hospitals and apartment complexes launching the rockets and mortars which will inevitably produce piles of telegenic dead Palestinians. Will the international potentates have any more sympathy for Israel when this happens than they did when it happened in Gaza City and Khan Yunis?