"The proliferation of weapons like the S-400 and its S-300 predecessor pose a serious challenge to US and allied air power," Dave Majumdar, defense editor for the National Interest, writes. "Both weapons systems are highly mobile, networked and can protect vast areas. Effectively, weapons like the S-400 and S-300 make an entire region inaccessible to conventional non-stealthy combat aircraft."
This "problem" is "going to get worse over time" as countries such as Iran will obtain similar weapon systems, Majumdar claims, adding that the Islamic republic has already begun to receive "a version of the S-300."
"Only the Lockheed Martin F-22 Raptor, F-35 and Northrop Grumman B-2 Spirit stealth bomber would be able to operate inside areas protected by those weapons. But even those aircraft could be challenged if there were enough S-300 or S-400 batteries operating as part of an integrated air defense network," the author concludes.
The S-400 Triumf (NATO reporting name: SA-21 Growler) is Russia's next-generation air defense system, carrying three different types of missiles capable of destroying aerial targets at short-to-extremely long range.