On January 22, Chinese government media angrily accused the U.S. of “wantonly provoking trouble” in the South China Sea.

The alleged American provocation? On January 17, the U.S. Navy’s USS Hopper, a guided missile destroyer, passed within 12 miles of Scarborough Shoal — a sea feature within Filipino territory that China now calls Huangyan Island.

Got that? Within Filipino territory, but China claims it.

Despite a 2016 ruling by the Hague’s Permanent Court of Arbitration that China’s shenanigans in the South China Sea have violated the Philippines’ Exclusive Economic Zone, Beijing asserted the Hopper’s action violated sovereign Chinese territory.

It gets worse. Someone in China’s defense ministry deemed the American ship’s passage a dire threat and dispatched a Chinese navy frigate. The Chinese warship then “drove it (the Hopper) away with a warning.”

Beijing’s propaganda portrays the incident as a near-clash of nuclear-armed giants. A warship belonging to the U.S. violated sovereign Chinese territory. The brief cruise was so ominous an outrage that China risked starting a war.

Most American and European media dismissed China’s reactions to a rather routine U.S. Navy Freedom of Navigation Operation as political theater.

However, completely dismissing China’s response as theatrics is a mistake,

In the very short term, Beijing’s harsh rhetoric and belligerent portrayal of the incident should dash any Pollyanna theories of an East Asian “peace” vacation prompted by South Korea’s Winter Olympics. No matter the immediate circumstance, one should never underestimate a military incident’s potential for serious political consequences. The April 2001 collision between a U.S. Navy recon plane and a Chinese fighter-interceptor provides a relevant historical example.

Unfortunately, China’s allegations and rash military reaction send a dangerous message well beyond the Olympics. During the past two decades, China’s Communist government has increasingly emphasized nationalist political themes. Territorial expansion in the South China Sea is a demonstrable hardline nationalist policy made concrete.

With good reason the Philippines contests China’s claims to its territory. In 2012, Scarborough Shoal (in the Spratly Islands) was a reef, a “sea feature” well inside long-recognized Filipino territory. The shoal is about 250 kilometers from the large inhabited Filipino island of Palawan. It is 1,200 kilometers from China.

Bullying its weak Filipino neighbor, China seized the area. In May 2013, a Chinese general said China would secure its South China Sea territorial claims by wrapping them with ships, air patrols and garrisons, the military “layers” akin to protective cabbage leaves. Cabbage has sprouted around Scarborough Shoal. There are now reports of Chinese “developmental activity” in the area — meaning preparation to construct an island.

It is a slow but steady invasion. Chinese companies create “territorial facts.” Using dredges and lots of concrete, construction teams turn what geographers call “features” (rocks, shoals, etc.) into man-made islands with bases. It’s literally concrete nationalist territorial expansion.

China’s claims are as ridiculous as they are enormous. In May 2014 China and Vietnam squared off over a Chinese oil-drilling project in Vietnamese waters. Vietnam saw the expedition as another step toward extending Chinese sovereignty to the “nine-dash line. ” This maritime boundary defines China’s claims. It dips south hundreds of kilometers from China’s coast to near the island of Borneo and encroaches on territory belonging to the Philippines, Vietnam, Malaysia and Brunei. Beijing’s jaw-dropping claim includes roughly 90 percent of the Sea’s 3.5 million-square-kilometers.

China is now demanding that foreign ships, like the USS Hopper, receive permission to pass through the region. The U.S., however, objects. Washington regards freedom of navigation (air and sea right of passage) as a vital global interest and actively opposes maritime territorial claims that intrude on recognized international shipping lanes.

As 2018 begins, in the South China Sea Chinese power is colliding with American power. Beijing’s latest behavior in the Hopper incident indicates it intends to enforce its spurious territorial claims — land and maritime — no matter the opponent.

And that is ominous.

Austin Bay is a syndicated columnist and author.

Austin Bay