WASHINGTON — When unveiling the Pentagon's fiscal 2017 budget request, Secretary of Defense Ash Carter highlighted the challenge presented by China as one of "our most stressing competitors."

"We're making all these investments that you see in our defense budget that are specifically oriented toward the checking the development of the Chinese military," Carter said Feb 2.

Two weeks later, China has now set up a pair of HQ-9 air defense systems on Woody Island, part of the Paracels chain of islands in the South China Sea. The move is the latest in a series of Chinese actions to assert dominance in the region, including rapid growth of a series of artificial platforms in the Spratley Islands, territory claimed by five other neighbors, including nearby Vietnam.

The weapons' placement also comes after the US has conducted a series of "freedom of navigation" exercises near the Spratleys, which officials have said explicitly are being done to prove to China that the territory remains in international waters.

Ben FitzGerald of the Center for a New American Security agrees that the HQ-9s by themselves "won't impede" American capabilities in the region, but adds that the deployment "confirms the Pentagon's concerns that this is an emerging concept that will be replicated throughout the region, which would impose significant operational challenges on US Forces."

China's actions "certainly support the rationale" that the Pentagon is right to focus on the Anti-Access/Area-Denial (A2/AD) challenge, FitzGerald added.

The Pentagon's fiscal 2017 request included around $3 billion in A2/AD technology development as part of the third offset strategy championed by Carter and Deputy Secretary of Defense Bob Work. It also features a heavy focus on taking existing munitions, such as the Tomahawk weapon, and adding new capabilities.

Such technologies would be key in defeating systems such as the HQ-9 in the event of a direct conflict, with US forces either needing to launch weapons while staying out of the roughly 125 mile radius of the system's missiles or relying on stealthy planes such as the F-35 joint strike fighter to penetrate the protected airspace.

While that range is not devastating to American capabilities, the deployment of the system, along with its "advanced radar capabilities for targeting, again support the Pentagon's narrative of challenges associated with competitors possessing precision weapons," FitzGerald noted.

Robert Martinage, a former undersecretary of the Navy now with the Center for Strategic and Budgetary Assessments, says the weapon placement is not a game-changer in and of itself, but "it could be the canary in the coalmine, a harbinger of what's to come."

If China expands its deployment of advanced defenses, Martinage said, it would have "significant operational implications" for the US and its allies. In peacetime, it could lead to China painting US planes with radar, increasing the risk of an incident; in a combat situation, it would put nearby assets at direct risk.

It also includes political impacts, Martinage added, noting it is "just another step in [China's] game."

"Little incremental provocations ... ultimately lead to where they want to go, which is asserting their sovereignty over most of the South China Sea," he said. "The question is, What do we do about it? I think we continue to do the freedom of movement navigations. But beyond that there's not a whole lot we can do. It's a little of a fait accompli, and the question is what's next."

Email: amehta@defensenews.com

Twitter: @AaronMehta

Aaron Mehta was deputy editor and senior Pentagon correspondent for Defense News, covering policy, strategy and acquisition at the highest levels of the Defense Department and its international partners.

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