The Assads have been threatening to take back the Golan ever since they were disciplined like errant schoolchildren in the Six Day War. That said, Syria's recent and aggressive mobilization on Israel's border makes the recent threats seem more serious. Certainly the IDF is taking it seriously:

Or course, that assumes that Israel will have those troops available to fight that war at that time. Any war with Syria will probably be preceded by some Hezbollah stunt designed to draw out Israel's forces into Lebanon. Even if that's not how it starts, you can be quite certain that Hezbollah will make its presence felt once Israeli and Syrian forces engage each other. Syrian generals haven't been spending time in Tehran for nothing.

Of course, any situation involving an actual invasion of Israeli territory definitionally represents an existential threat. That means that the IAF is let off the leash in terms of degrading Hezbollah's infrastructure, to say nothing of what will happen to Damascus. The calculus between military force and international condemnation changes when the alternative is the destruction of Israel.

References:
* Syria Reorganizing Their Military Hezbollah-Style, Moving SCUDS To the Border To Target Israeli Population Centers [MR]
* IDF prepares for Syrian attack on Golan [JPost]
* This Summer's War With Syria, Iranian Coordination Edition [MR]

Previously:
* Syria is Hiding Weapons in Civilian Aid Convoys. Of Course They Are.
* Screw Syria
* Who's Sending Arms to Hezbollah and Syria Today?

Cross-posted to:
* Israpundit