U.S. Secretary of Defense Chuck Hagel calls China's actions in a near-collision in the South China Sea irresponsible. He also warned that such incidents could aggravate tensions in the region. This latest episode could test the increased U.S. emphasis on Asia.
The crew of the USS Cowpens was observing the Chinese carrier Liaoning on December 5, and Secretary of Defense Hagel says that's when another Chinese vessel cut across the bow.
"That action by the Chinese, cutting in front of, their ship, 100 yards in front of the Cowpens was not a responsible action. It was unhelpful, it was irresponsible," said Hagel.
A Chinese Foreign Ministry spokeswoman downplayed the incident.
"China has always respected normal naval and air passage and freedom of navigation, which is in line with international law," she said.
U.S. ships monitor Chinese activities from international waters in the South China Sea and the East China Sea.
China finds that unacceptable, says Rick Fisher, senior fellow at the International Assessment and Strategy Center.
"In both areas, the Chinese air and naval forces have tried to interfere with American intelligence collection, and I expect that this kind of cat-versus-mouse contest will continue. And, if the Chinese decide, it could get rough," said Fisher.
At the Pentagon, Secretary Hagel says such confrontations are risky.
"What we don't want is some miscalculation here to occur and when you have a Cowpens issue that's the kind of thing that's very incendiary that could be a trigger or a spark that could set off some eventual miscalculation," he said.
Asia expert Richard Cronin agrees.
"There's a high possibility of some incident, which probably wouldn't escalate into a war between the U.S. and China but could certainly involve some shooting and leave a lot of diplomatic wreckage behind," said Cronin.
Cronin, who directs the Stimson Center's Southeast Asia Program, says China also is projecting power by declaring an air defense identification zone in the East China Sea over islands administered by Japan.
"So it's all about pushing us out, and it's also about trying to expand the rights it's entitled to," he said.
The U.S. rejects the air defense zone. As part of the Obama administration's so-called Asia pivot, Secretary of State John Kerry recently visited Vietnam and the Philippines, pledging $70 million in security aid.
"The zone should not be implemented, and China should refrain from taking similar unilateral actions elsewhere in the region, and particularly over the South China Sea," said Kerry.
Rick Fisher says China's military buildup helps justify Washington's pivot.
"But as China ramps up its actions, as it increases its pressure, it is in turn putting more pressure on the United States to reconsider defense cuts, to reconsider its strategy and to accelerate military preparations," he said.
With increased U.S. and Chinese military activity raising the potential for accidental clashes, Asian neighbors Japan, Taiwan, Vietnam and the Philippines remain on guard.