China has responded to an "unusual" flight by a US transport aircraft by sending its combat jets into Taiwan's airspace. Taiwan says it had to "forcibly" remove them.
Communist China considers Taiwan its sovereign territory. Taiwan – never conquered during the 1949 Cultural Revolution – does not.
Chairman-for-life Xi Jinping, however, has repeatedly asserted his intention to bring the island under Beijing's rule – by any means necessary.
So when the US Navy sent a transport aircraft down the west coast of the democratically governed island this week, Beijing took insult.
It responded by sending a flight of Russian-designed Su-30 "Flanker" interdiction fighters into Taiwanese airspace.
"The US warplane's rare flight over Taiwan showed the increasing collaboration between the US military and Taiwan secessionists, and the Chinese mainland's fighter jet sorties and approaches sent them a powerful warning and demonstrated how much the PLA [People's Liberation Army] was determined and prepared for war," Chinese Communist Party (CCP) mouthpiece the Global Times declared the following day.
Taiwan's Ministry of Defence says the Chinese fighters were given verbal warnings before its own US-built F-16 Viper fighters "drove away" the intruders.
The trigger for the confrontation was the presence of a US Navy C-40A "Clipper" transport aircraft – a militarised version of the commercial Boeing 737 passenger jet. It had flown an approved, though unusual, flight path over Taiwan's airspace on its way to Southeast Asia from the significant US base at Okinawa.
The flight was always going to upset Beijing.
"The PLA's fighter jet sorties and approaches to Taiwan is likely a counter to the provocative move by the US military aircraft," CCP military spokesman Song Zhongping told the Global Times. "This can also be seen as a de facto joint military drill, indicating the US could lend Taiwan support in a war and give Taiwan secessionists courage to fight the mainland."
Song said the Chinese incursion was deliberate.
"This time they flew to the southwestern "airspace" of the island, which showed the determination and capability of the PLA, and this will become more frequent and routine."
That the US Navy flight was an overt signal of support for Taiwan is likely, especially given China's recent major military exercises close to its borders. The new aircraft carrier Shandong has been testing its weapons systems to the southeast of the island in what international observers say has been a clear "signal" to Taipei.
Taiwan has repeatedly complained in recent months that China has been stepping up military activity in its vicinity. It sees this as a deliberate attempt to menace the newly elected democratic government of President Tsai Ing-wen.
Beijing insists such exercises are nothing unusual, and that they are happening in its own territory anyway.
But there is no denying China is rattling sabres in its relationship with Taipei. Last month, senior People's Liberation Army spokesman Wu Qian told a CCP assembly that "Taiwan is an inalienable part of China, and that the Taiwan question is China's internal affair, and China will not accept any foreign interference".
"The PLA has the firm will, full confidence and enough capability to thwart any kind of secessionist attempt by foreign forces, and will take any necessary measures to safeguard national sovereignty and territorial integrity and maintain peace and stability across the Taiwan Straits," he said.
The United States has stepped up its naval presence in the vicinity of Taiwan and the South China Sea in recent months. It sent a destroyer, the USS Russell, through the Taiwan Straits last Thursday. This was the seventh transit of the disputed waterway so far this year.
Washington has adopted an increasingly overt attitude to the international status of the East and South China Seas, as well as the Taiwan Strait. It insists it has no opinion over who owns what islands or reefs, only that this be negotiated and administered under the United Nation's laws of the sea.
Specifically, that means the freedom of navigation of commercial and military vessels through international waters.
The US ambassador to the UN has this week upped the ante. He rejected Beijing's assertion that it has the right to expel Malaysian resource exploration ships from the South China Sea. "The United States rejects these maritime claims as inconsistent with international law as reflected in the 1982 Law of the Sea Convention," Ambassador Kelly Craft wrote in a diplomatic submission.
Malaysia is seeking approval from the UN to expand the definition of its continental shelf in its favour. Beijing is continuing to ignore a 2016 ruling by the international Permanent Court of Arbitration which rejected its claims to the entire South China Sea as unfounded.
A tense three-way standoff between Chinese, Vietnamese and Malaysian forces dragged out over several months earlier this year. At the heart of the dispute was a Malaysian survey platform.
The Australian frigate HMAS Parramatta joined forces with the USS America stealth-fighter carrier, the cruiser USS Bunker Hill and the destroyer USS Barry in April for a freedom-of-navigation demonstration. It was in response to Chinese warship manoeuvres surrounding the Malaysian operation.
"To bring this much combat capability together here in the South China Sea truly signals to our allies and partners in the region that we are deeply committed to a free and open Indo-Pacific," US Rear Admiral Fred Kacher said at the time.
Driving nations together
Beijing's increasingly assertive actions on its borders with India, Vietnam, the Philippines and Malaysia has only been serving to drive the nations together.
Manila has reversed its threat to scrap its military relationship with the US "in light of political and other developments in the region".
Kuala Lumpur has taken its territorial dispute with Beijing to international arbitration.
Jakarta has rejected calls by Beijing to arbitrate a dispute over fishing rights. Indonesia asserts Beijing isn't its neighbour anyway and therefore didn't qualify for such provisions under international law.
India, facing Chinese incursions in its highland borders, is also moving to strengthen ties with Australia. New Delhi and Canberra have just signed a $12.7 cyber defence pact as well as an agreement for the militaries of each nation to use each others' bases and facilities for repair and replenishment.
Canberra itself has been subject to immense intimidation from Beijing, including trade tariffs and threats to withdraw Chinese students, over its resistance to aggressive diplomatic and economic policies.
Such growing co-operation among Southeast Asian and West Pacific nations present a severe setback for Beijing's 'wolf-warrior' diplomacy.
While its military forces – mainly its navy – has been growing dramatically in recent years, it remains incapable of going head-to-head with US forces for at least another decade.
However, if nations such as Japan, the Philippines, Malaysia, Vietnam, Indonesia, Australia and India ally to counter Beijing's aggression, its forces will be significantly overmatched.
Jamie Seidel is a freelance writer | @JamieSeidel