I don’t think “the west” has any interest whatsoever in getting involved in any military activity in Syria.
According to Galrahn’s tweets, one of the Russian ships is a naval rescue ship. I think they might be concerned with protecting/extracting Russian military/civilian personel in Syria in the event of a full scale civil war. I don’t think they are worried about NATO getting involved.
Hard to predict what will happen there though, very different situation to Libya.
Hard to see how this one plays out. I think the Hezbollah-card is eroding the more Arab blood Assad sheds. Would he try to provoke an Israeli response to save his neck. An IRBM strike or Golan land grab to rally the flag.