I think this is the answer to my question last week - why did Russia with the best intelligence on Syria start pulling out its citizen's all of a sudden
They knew something was bigger going down (had to be a war btw Syria and Israel or Turkey or the start of significant chemical warfare btw Assad and the rebels) They knew that Assad no longer had the resources to secure certain conventional and chemical weapons - that Israel did not want to be transfered to Hizbollah (also at war with Israel). Assad also lacked the power to keep saying no to Hizbollah, whom he now needs to help him out. They knew these weapons would start being transfered and that Israel would react. (note explosian at Hezbollah weapons depot last week). They may also know that Assad and Khomenei see it in there interest to start a war with Israel eg modus operandi for Arab dictators/Royalty to distract unhappy populace - start hostilities with Israel.
Not in Israel's self interest to start a war - their best option is to keep out of the mess. But with the significant possibility of an attack/distraction from Hezbollah, they also can't allow Hezbollah to get significantly more potent weapons to point at their cities.
That is probably why Israel circulated it hit a convey of arms to Hezbollah instead of a chemical weapons depot (research facility for improving Syria's resistance capability). It was a message that they really really did not want certain weapons to be given to Hezbollah - as they have stated numerous times recently but less forcefully
