MELBOURNE, Australia, and BEIJING — Activity by U.S. military ships and surveillance planes directed toward China has increased significantly under the Biden administration, a spokesperson for the Chinese Defense Ministry said April 29.

As an example, Wu Qian said the U.S. Navy’s Arleigh Burke-class destroyer Mustin recently conducted close-in observation of the Chinese aircraft carrier Liaoning and its battle group.

That had “seriously interfered with the Chinese side’s training activities and seriously threatened the safety of navigation and personnel on both sides,” Wu said. The ship had been warned to leave and a formal protest filed with the U.S., he added.

Compared to the same period last year, activity by U.S. military ships was up 20 percent and by planes 40 percent in areas China claims as its territory since President Joe Biden took office in January, Wu said. At the same time, China is continuing to modernize its military across all domains amid what it considers diverse and complex security threats and challenges from foreign actors.

China routinely objects to the U.S. military presence in the South China Sea, which it claims virtually in its entirety, as well as the passage of Navy ships through the Taiwan Strait.

The country recently marked the 20th anniversary of the collision between a U.S. surveillance plane and a Chinese naval fighter jet near the Chinese island province of Hainan that resulted in the Chinese pilot’s death. He was called a hero who sacrificed himself for the defense of the motherland. The U.S. maintains its plane was in international airspace, describing the event as an accident caused by reckless flying on the part of China.

The ‘gravest immediate threat’

But Taiwan remains a top focus for the Chinese government.

The government’s most recent defense whitepaper stated that global and regional security threats are on the rise, including cyber and biological threats as well as piracy. In addition, separatist forces supported by external parties in places like Tibet continue to pose “threats to China’s national security and social stability,” according to the document.

The whitepaper also acknowledged that a series of territorial disputes in the Asia-Pacific region, including those involving China, remain unresolved, though the government took a relatively sanguine view on the matter. (These statements came before last year’s fatal clashes between Chinese and Indian troops along their disputed mountainous border.)

However, the document called the Taiwanese government’s independent approach from the mainland the “gravest immediate threat to peace and stability” in the Taiwan Strait and the biggest barrier to the peaceful reunification of China.

China views the self-governing island of Taiwan as a rogue province and has vowed to reunify it with the mainland by force if necessary. The island has experienced de facto independence since 1949, when Chinese nationalist forces fled there following their defeat to communist forces in the Chinese civil war.

The U.S. maintains only unofficial relations with Taiwan in deference to Beijing but provides the island with defensive weapons and is legally bound to treat threats to it as matters of “grave concern.”

In an interview with Britain’s Sky News, Taiwanese Foreign Affairs Minister Joseph Wu reiterated recent warnings that the military threat from China is growing through “misinformation campaigns, hybrid warfare, and ... gray zone activities” – something he said appears to be part of preparations for a “final military assault against Taiwan.”

China which has repeatedly warned that any move toward formal Taiwanese independence is a red line that could trigger an invasion. That red line could fall well short of an actual, formal declaration of independence, however, and could instead be triggered by U.S. activity that China views as supportive of Taiwanese independence, according to Collin Koh, a research fellow at the Institute of Defence and Strategic Studies at the S. Rajaratnam School of International Studies in Singapore.

Koh said the stationing of American forces on the island is one example of a move that could anger Chinese leaders.

A scenario in which Taiwan is invaded is widely seen as a key driver behind the massive modernization effort of the Chinese People’s Liberation Army.

However, the consensus – among experts testifying at February hearings held by the congressional U.S.-China Economic and Security Review Commission – is that China itself would be unable to mount a full-scale invasion of the island across the Taiwan Strait, mainly due to its inability to send enough forces by sea or to ensure a successful initial landing, even with requisitioned civilian vessels.

Nevertheless, China is working to address an amphibious capability gap, with six Type 071 landing platform docks already in service that were recently joined by a larger Type 075 landing helicopter dock, with at least two more being built.

A buildup at sea

Looking farther south, China’s whitepaper said the “situation of the South China Sea is generally stable and improving as regional countries are properly managing risks and differences.” However, it left unaddressed the fact that China has largely completed its fortified reclaimed islands in the body of water. Those islands now have airfields, ports, early warning radars, and defenses against air and seaborne attacks, serving Beijing’s interests well, Koh said. They have also enabled China to maintain a sustained presence in Vietnam’s exclusive economic zone.

He did concede that the size of each outpost would require a significant amassing of munitions to neutralize them in a conflict. Other observers have questioned whether the U.S. has sufficient munitions to spare against these facilities during a high-intensity conflict when there are many other potentially more important targets.

In an evening address to Congress on April 28, Biden did not directly address military threats from China, but he emphasized that the Asian nation and others were “closing in fast” in economic and technological terms.

“We’re in a competition with China and other countries to win the 21st century,” he said.

Mike Yeo is the Asia correspondent for Defense News.

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