the israelis just randomly bomb syria and the russians do not like it. if the russians felt a need to respond, would it look like a sneak attack by hamas?
the situation is messy, but the truth is that iran is a russian protectorate and is in many ways treated by moscow like a former ssr. a greater russian sphere includes iran. that aligns hamas pretty squarely with moscow, nowadays, which provides the pentagon with a good reason to seek it's destruction.
the russians must have at least known what was going on and the american response indicates legitimate concern about a potential russian distraction tactic. they did this once before.
it's a different analysis, but you'll note that america's immediate response was to send war ships to israel, and that's exceedingly curious.