The US, despite being a big power outside of South China Sea, remains to be a big player in the regional affairs, said Zhou Bo, a senior research fellow with Tsinghua University, at a seminar on Oct 27.

"The situation in the South China Sea has not changed much," said Zhou. "While the greatest change and dynamic of the issue is that the United States ended the war in Afghanistan and shifted its focus to Indo-Pacific."

The Sino-US competition will continue intensifying because the US will accelerate its efforts to check China's rise in the next decade.

To target China, Zhou said, the US has planned Quad, a quadrilateral security dialogue with Japan, Australia and India, and AUKUS, with Australia and the United Kingdom.

Quad has been established as a soft deterrence and it may not impose severe pressure on China. The negative influence of AUKUS remains to be observed as it's in the making. But one thing is clear, AUKUS, of which the pact included to facilitate Australia's development of nuclear-powered submarines, has damaged nonproliferation.

"The US alliance system has been falling apart", said Zhou. Zhou mentioned that with more attention shifted to Asia-Pacific and withdrawal from multilateralism, Washington may neglect Europe to some extent.

Therefore, US allies will reconsider the independence of development. Meanwhile, Asian countries are not interested in taking sides.

Zhou also said, "the North Atlantic Treaty Organization has not figured out a clear path after World War Ⅱ so it can survive but will not thrive."