Russia's full-fledged ring of air defences has prompted Washington "to rethink its position as the world's undisputed air power", according to Wall Street Journal reporter Thomas Grove.
In his article titled "The New Iron Curtain: Russian Missile Defence Challenges US Air Power", the author noted that Moscow has already deployed its missile shield north from Syria, along the borders of Eastern Europe and in the Arctic Circle, in a move Grove claimed threatens "the reach of the US military".
In particular, Russia's S-400 missile system, "a nettlesome and potentially deadly missile shield, is changing the calculus of the US and its allies in potential hot spots, beginning its deployment in Syria", Grove argued.
In this context, he referred to Washington's concerns that by selling the S-400 systems to other countries, Russia further expands its ability to deter the US military.
Separately, the author singled out current efforts by Russian arms manufacturer Almaz-Antey to develop a more sophisticated model, the S-500, designed to tackle enemy hypersonic aircraft and new-generation intercontinental ballistic missiles.
In October 2017, Sergei Kornev, the head of Rosoboronexport’s Air Force Special Equipment and Service Export Department, said that the S-400 systems are operating in Syria faultlessly, which leads to an increased interest from Middle Eastern countries in terms of S-400 purchases.
The system integrates a multi-functional radar, autonomous detection and targeting systems, as well as anti-aircraft missile systems, launchers, and a command and control centre.