This week two stories from different sides of the world reminded US air power advocates why achieving Air Superiority may be more difficult in the 21^st Century than it was at the tail end of the last century. First, it was widely reported that China deployed indigenously produced modern long-range surface-to-air missiles (MLR SAMs) system, the HQ-9 (known is China as the hóng qí, or “red flag”) to Woody Island, a small land mass in the Paracel Islands claimed by China, Taiwan, and Vietnam.

Hours after the initial report of China’s HQ-9 deployment, Russian officials announced it would commence S-300 (NATO Designator: SA-20 GARGOYLE) deliveries to Iran (later reports indicated a disagreement over payment may lead to a delay in delivery. Coming just months after Russia deployed an S-400 (NATO Designator: SA-21 GROWLER) to Syria, these stories emphasize the expanding problem of deployment and proliferation of MLR SAMs around the world.

What is it about these systems that concern air power planners? According to Dave Majumdar, Defense Editor for the National Interest, the HQ-9 has the capability of engaging six simultaneous targets to a maximum range of 120 nautical miles, at a maximum altitude of 90,000 feet.

Majumdar further contends that the system creates a de facto “no-fly zone” for all but low-observable (LO) aircraft such as the F-22 Raptor and the B-2 Spirit. According to AirPowerAustralia.net, the most upgraded variants of the S-300 have similar capabilities, and the S-400 provides even more capability against a variety of airborne targets, including LO aircraft and precision-guided munitions. These MLR SAMs are the epitome of Anti-Access / Area Denial (A2/AD) weapons that are designed to prevent the US and its allies from engaging in a given conflict, or if they do, severely restrict their freedom of movement in an armed conflict. The systems are designed to fundamentally alter the way air forces plan and execute air campaigns.

In his masterpiece on building an airpower campaign, titled simply The Air Campaign, Colonel (USAF ret.) John A. Warden emphasized the need to gain and maintain air superiority as a necessary first step in winning major force-on-force conflicts. For decades the US Air Force has built, equipped and trained a force of lethal fourth and fifth generation fighters to rout an adversary’s air force and quickly and decisively attain air superiority, more commonly known today in Air Force circles as “Air Dominance.” Operation DESERT STORM is the classic example of US air superiority, as coalition aircraft tallied a 36:1 air-to-air kill ratio, and systematically degraded and eventually destroyed the advanced Iraqi integrated air defense system (IADS). So thorough was US air dominance in 1991 that Iraq chose to bury its fighters rather than fly them in 2003 during the opening of Operation IRAQI FREEDOM shows how overwhelming and complete US air dominance was assumed.

Since the advent of air warfare the primary threat to air superiority has been adversary fighter aircraft. However, it has been recognized for decades that SAMs could at some point in the future become the biggest threat to air superiority. Colonel Warden introduced the theory of “Defensive Air Superiority”, which he defined as a situation “in which enemy air cannot operate over some part of one’s territory.” Such a scenario “could arise if a state were able to create a sufficiently strong ground-based air defense system. To date, no ground system has given this degree of protection, but it is theoretically possible.”

Ground-based air defense has made a revolutionary leap forward in the 28 years since Colonel Warden penned those words. Today, a strong argument can be made that ground-based air defense, in particular modern SAMs and the IADS that command and control them, is the primary threat to US and allied air superiority.

China and Russia are the only potentially hostile regional powers that have made a significant investment in building and maintaining the type of robust air force that would be needed to challenge US air superiority. Syria, Iran, and North Korea have not purchased new fighters in decades, and the MiG-29 FULCRUM, a fighter that was routed by US forces in DESERT STORM 25 years ago, is the most advanced fighter in each of those nations’ inventories.

Iran has been unable to recapitalize its fighter force and relies on Vietnam-era, US-built fighters. Syria’s primary fighters are 1970s and 1980s vintage Soviet-built fighters. North Korea’s fighter force is even more geriatric, with the bulk of its fighter force Chinese reverse-engineered Soviet fighters, including the J-5 (MiG-17), J-6 (MiG-19) and J-7 (MiG-21). These air forces are unlikely to present much of a challenge to US and European 4^th and 5^th Generation fighters, unlike the threat posed by MLR SAMs.

Russia and China have shown how the deployment of even a single MLR SAM system can rapidly create a localized A2/AD environment. Russia’s deployment of the S-400 to Syria days after Turkey shot down one of their fighter-bombers is just the most recent example of Russia sending an MLR SAM to rapidly establish an A2/AD environment over their troops or claimed territory.

In 2014, just days after the first Russian troops were seen on the ground in Ukraine’s Crimea Peninsula, an S-300 Battalion was deployed to Crimea to provide air defense protection for Russian forces on the ground. It appears that deployment of an MLR SAM is now part of Russia’s standard operating procedure to provide an umbrella of air defense protection for its forces.

China seems to have taken that page directly out of the Russian playbook with their deployment of the HQ-9 to Woody Island. Tensions in the South China Sea have been on the rise over the last year and China appears to have begun a program of militarization of the region, highlighted by the HQ-9 deployment, the first deployment of an MLR SAM to the South China Sea. China appears to be emphasizing its territorial claims in the region by deploying A2/AD assets to the region.

As Colonel Warden foresaw in 1988, technological advances in ground-based air defense have allowed nations such as Russia and China to not only develop capabilities to enable Defensive Air Superiority, but the ease of mobility of these systems allows this Defensive Air Superiority to be deployed to a contested region in a matter of days or even hours. It is likely more deployments and proliferation of MLR SAMs will be seen in the coming years and US and coalition air planners must prepare for operations inside of the A2/AD environment provided by these SAM systems. In a fundamental shift, MLR SAMs should now be considered the primary threat to US and coalition air superiority, surpassing that of adversary fighters.