This is coolbert:
Here with gratitude from several sources to include WIZARD and CORPORAL FRISK and the tip from Harry at Sharkhunters some details, Russian S-400 surface-air-missiles found to be less effective than thought.
Impenetrable defenses not so impenetrable? More or less copied from sources in entirety and unashamedly so:
"SYRIAN AIR STRIKE"
"When it comes to the defences, it is clear that the talk of the S-400 deployment in Syria creating an impenetrable A2/AD-bubble stopping western strikes was not correct."
"While many of the earlier Israeli strikes had taken place in areas which present difficulties for the S-400 (and supporting shorter-ranged systems) to see and intercept the targets, the strike waves approaching over the eastern Mediterranean would be more or less the perfect scenario for long-ranged SAM-systems, and is very similar to the set-up of systems operating from Kaliningrad which often are described as being able to deny NATO access to the Baltic Sea. While it likely was political will that stopped the Russian air defence systems from being activated, the Syrians did their best, with around 40 missiles having been reported by Pentagon as fired. While it is not impossible that some of the cruise missiles were intercepted, it is clear from the pictures that even this barrage of air defence missiles was unable to serious lessen the damage suffered by the Syrians. A significant issue was likely that all missiles struck their targets"
S-400 not so effective after all when deployed in real-world conditions?