I don't have the time to flesh this one out, but see if this makes sense. It is commonly assumed that the United States is Israel's only real friend and without the explicit support and assistance of the United States Israel would vanish. I think this may be true but misses an equally important point. The United States explicit support of Israel is the only thing keeping many Palestinians alive. If the United States starting acting towards Israel like, say, France, then Israel might feel its very existence and those of its citizens were quite legitimately at risk. I think their perspective might best be summarized as the Palestinian Authority, Hamas, Hezbollah, and a few other sordid groups would suddenly become, to use a cliche, a clear and present danger justifying some rather extreme acts.
I've heard people wonder out loud before what would have happened if every Jew in Warsaw had met the Nazis with a gun instead of allowing themselves to be herded into the ghettos and starved until they were beaten and bombed into submission. Somehow, I think those events are still far too close to forget and, to borrow another cliche, they are too deeply seared, seared into their memory to allow the Jews of Israel to sit back and wait for their mass slaughter.
Without the gaurantee of the United States to step in and help them deal with the forces arrayed against them, should that become necessary, do you really think the Israelis will passively wait to be ground down in a "proportional" war of attrition? I don't. I think they will act preemptively, as they did before in 1967, to eliminate the insane medieval mindset fanatics who sit on their doorstep threatening them and their children, figuratively and literally, every day. As their very survival becomes more threatened, the niceties of taking risks to spare the lives of those not in their tribe would go by the wayside. They would build a scorched earth moat if necessary to secure their survival. That's why I think the United States support of Israel is doing more to help the Palestinians than the Israelis.
Of course, I'm not saying that all Palestinians are insane or want to see all the Jews killed. But you are delusional if you think there isn't a substantial group of people, e.g. Hamas and Hezbollah, who quite explicitly call for this and would do it if they only could. Anyway, I'm sure I could find problems with this thesis but I wanted to get it down in the ether while I had a minute.