Is there anything that will cause Israel to go all out and defeat Syria? I’m not sure Israel is up for the fight, politically. It makes so much sense to eliminate the Syria/Iran threat.
The Israeli military failed to disable the non-state entity of Hezbollah during last summer's war. They have regrouped and still have thousands of rockets ready to fire against Israel again, and let's not forget, the kidnapped Israeli solider which started all that is still missing. So this Israeli government doesn't have the stomach to face another mess with an enemy with a lot more ability than Hezbollah.
If there's a change in leadership in Israel, then you might see a change in attitude.