SAM sites in the Bekka are not the same as missile bases dispersed throughout Syria, the US sure didn't have much luck targeting SCUD launch facilities in GW1, don't really see Israel having much luck either against the Syrians if it came to that
Got the number two man in Hezbolla according to report by Fox
Simply put, If Syria attacks and fails, the leadership has nowhere to run these days...
They are surrounded by enemy, or western-friendly countries (turky and Jordan) who would know the benefits of handing them over...
They may bluster to meet the expectations of thier Iranian moeny-lenders, but that's about it, I believe....