BEIJING/WASHINGTON -- Sino-American tensions in the Indo-Pacific region have risen to heights not seen in decades as China fired four ballistic missiles into the South China Sea on Wednesday, while U.S. Defense Secretary Mark Esper embarked on a trip to Hawaii, Guam and Palau, where he will visit naval ships taking part in a massive maritime exercise.
The missiles were fired into a no-fly zone between the Paracel Islands and the Chinese island of Hainan, according to U.S. media reports.
The missiles used reportedly include DF-26 missiles, which are capable of reaching Guam, and a DF-21D anti-ship weapon for use against aircraft carriers, sending an apparent signal to Washington.
"China's firing of medium-range missiles in the South China Sea is part of its drills to counter the U.S. Navy-led RIMPAC exercise now taking place off the coast of Hawaii," said Toshiyuki Ito, a retired vice admiral in Japan's Maritime Self-Defense Force and now a professor at the Kanazawa Institute of Technology.
In particular, the use of the "carrier killer" DF-21D "can be considered a message to the U.S. that it can attack its carriers at any time," said Ito, who called the launch "a symbol of China's anti-access/area denial strategy" in the region.
In a speech Wednesday in Hawaii, Esper warned that "the People's Liberation Army continues to pursue an aggressive modernization plan to achieve a world-class military by the middle of the century. This will undoubtedly embolden the PLA's provocative behavior in the South and East China seas, and anywhere else the Chinese government has deemed critical to its interests."
Esper reiterated his call for a united front to contain the threat posed by China.
"Our robust network of allies and partners remains the enduring asymmetric advantage we have over near-peer rivals, namely China, that attempt to undermine and subvert the rules-based order to advance their own interests, often at the expense of others," he said.
Esper talked by phone that day with Papua New Guinea Defense Minister Saki Soloma in what the Pentagon described as "a historic first call between the defense counterparts." The two men "spoke to the importance of upholding international rules and norms and their commitment to defending a free and open Indo-Pacific region," its readout said.
Esper is expected to meet with Japanese Defense Minister Taro Kono in Guam later this week in a show of unity among the allies.
The American defense secretary's trip to tiny Palau -- one of the 15 countries left that still have diplomatic relations with Taiwan -- demonstrates the Trump administration's desire to cultivate friendships for countering China in the region.
The latest test comes amid an escalating war of words between Washington and Beijing, which Chinese Defense Ministry spokesperson Wu Qian explicitly referenced to reporters Thursday.
"Some U.S. politicians have tried to undermine U.S.-China relations for the sake of their own interests before the presidential election," Wu said. This was likely a swipe at Trump administration officials, including Secretary of State Mike Pompeo and Esper, who have ramped up criticism of Beijing in recent weeks.
An article in the Chinese Communist Party's Global Times hinted that the launch may have come in retaliation for an American U-2 reconnaissance aircraft passing on Tuesday through a no-fly zone set up for its live-fire drills.
The piece cited analysts as saying that Beijing's establishment of another "navigation restriction zone" the following day was "designed to send the U.S. a clear message that the U.S. would need to assume all responsibility if its reconnaissance aircraft got mistakenly shot down" on another such flight.
Meanwhile, Wednesday's missile launch and the heightened Sino-American tensions have left other countries in the region in a difficult spot.
The Philippines, not wanting to be drawn in, had naval chief Giovanni Bacordo say the firing was "way beyond" the West Philippine Sea and thus did not violate the country's territorial rights.
The Indonesian and Malaysian foreign ministries had not commented as of Thursday afternoon.
Though Vietnam did not comment specifically on the launch, it issued a statement Wednesday condemning the exercises near the disputed Paracels, which Hanoi claims, as violating its sovereignty over the archipelago.
Foreign Ministry spokesperson Le Thi Thu Hang said in a statement that China's actions undermined ongoing negotiations between Association of Southeast Asian Nations members and China on a maritime code of conduct for the South China Sea.
This is hardly the first time that military tensions between the U.S. and China have risen. In March 1996, in the run-up to Taiwan's first direct presidential election, China held military exercises and fired missiles in a show of force near the Taiwan Strait. Then-U.S. President Bill Clinton responded by sending two aircraft carriers, after which the situation settled down.
U.S. Adm. Philip Davidson, commander of the Indo-Pacific Command, said shortly before taking over in 2018 that "China is now capable of controlling the South China Sea in all scenarios short of war with the United States."
American and Chinese forces encounter each other in the South China Sea multiple times a day, which adds up to thousands of contacts a year, heightening the risk of an accidental conflict.
"The U.S. and China will continue moving to check each other in the South China Sea," said Tetsuo Kotani, a professor at Japan's Meikai University. "Neither wants a military confrontation. This probably won't change the situation dramatically."
"We don't want a clash with the U.S., but we can stay silent for only so long when faced with provocations," a Chinese military source said.
Additional reporting by Cliff Venzon in Manila.