Israel worries about Syria

"If the Assad government falls, that puts another player in the game – an unknown government - something that Israel is not likely to accept." Israel wants Al-Asad to stay in power, hopefully a much weakened one from which they could pull more concessions out of (that is, concessions to Israel of course). However they (and the Americans) might move against him if his position seems untenable (which it isn't yet) and try and get a cosmetic change. Don't think if one day they out of nowhere start calling for Bashar to go that that means they've turned against the regime. They know the present Syrian regime although not exactly to their liking is probably the best they'll get in Syria for them.