“One has to wonder, then, why Israel wants Assad out. “
I don’t think Israel has done anything to support Assad, as support from Israel would be his death knell. Neither have they done anything obvious to dislodge him. Assad was a secular leader and the Christians support him as they could exist and probably prosper under his leadership. I think in that last sentence you see Obama’s and Hillary’s hatred for Assad; he was secular and the Christians support him. As for Israel, I am fairly sure they know where he is and have the bunker buster capability to kill him if they wanted to. They have done nothing, which in the Middle East is ringing support.
Israel regularly bombs Syria.