So you support a country who is neutral towards ISIS killing soldiers that are fighting ISIS?
Took me a while to figure out what you were trying to say, but I’ll give it a try.
The Syrians are just as anti-Israel as the rest of the characters fighting there, but they are tied up fighting ISIS, the SDF (supposedly our friendlies), etc.
Meanwhile Iran was trying to occupy part of Syria so as to build a run system from their country all the way into Lebanon, a good part of which they control by their genocidal proxies, Hezbollah (who are actively fighting against Israel and anyone else Iran says to fight).
Throw in some Hamas fighters in Syria (again, active genocidal enemies of Israel) and you have a real Hungarian Goulash of extremists fighting each other when they are not fighting Israel.
Therefore Israel has to pick key threatening targets in Syria including Syrian CBW and nuclear weapons development facilities, anti-aircraft sites protecting Hezbollah training and staging facilities/arms depots, and some Al Qaeda/ISIS targets if they get too close to the Israeli border.
As Mr. Spock would say about the Israeli strikes - “Logical”.
See: the answer to your question is easy to answer if you have a scorecard about who the players are.