The Aviation Geek Club:
The Russian Military have put their S-400 air defense system on alert in Syria to deal with potential Israeli Air Force (IAF) F-35I and F-16I air strikes inside the country, defense analyst and author Babak Taghvaee said on Twitter on Sep. 20, 2019.
According to Taghvaee, the Russian Air and Space Force (RuASF) may allow Israel to attack Hezbollah and Iranian targets in Syria; however, they take a different approach when it comes to the Syrian Arab Army (SAA).
He also highlighted the most recent incidents in which Russian jets reportedly blocked Israeli warplanes from bombing Syria Sep. 18 and 19.