[SINGAPORE] China risks erecting a "Great Wall of self-isolation" in Asia over its actions in the disputed South China Sea, US Defense Secretary Ash Carter told a global defense forum in Singapore.
"There is growing anxiety in this region, and in this room, about China's activities on the seas, in cyberspace, and in the region's airspace," Mr Carter said on Saturday in a speech to the Shangri-La security dialogue. He called China's land reclamation in the South China Sea "unprecedented" and urged it instead to join the US in cooperating on security in Asia.
"Countries across the region have been taking action and voicing concerns publicly and privately, at the highest levels, in regional meetings, and global fora," he said.
"As a result, China's actions in the South China Sea are isolating it, at a time when the entire region is coming together and networking. Unfortunately, if these actions continue, China could end up erecting a Great Wall of self-isolation."
China's assertion to a large swath of one of the world's busiest shipping lanes pits it against a gaggle of smaller South-east Asian states who also claim parts of the South China Sea, through which more than US$5 trillion in seaborne trade passes the year. The area has become a flash point for a broader rivalry between China and the US - which is not a claimant - for influence in the western Pacific.
In recent years, China has reclaimed more than three thousand acres in the waters and beefed up its military presence, while saying its activities in the area are also designed for civilian purposes like search and rescue. In turn, the US has resumed freedom of navigation operations in the South China Sea, where its ships sail close to islands and reefs claimed by China and other nations.
The forum comes amid a climate of friction over China's actions, with the US accusing two Chinese fighter jets of conducting an unsafe intercept last month of a US surveillance plane in international waters, and with an international tribunal expected to rule soon on a Philippine challenge to China's South China Sea claims.
In response to a question after his speech, Mr Carter warned China against building on the Scarborough Shoal, a prospect raised by chief of US naval operations Admiral John Richardson in March. The uninhabited shoal was seized from the Philippines in 2012.
"I hope that this development doesn't occur because it will result in actions being taken both by the United States and by others in the region which will have the effect of not only increasing tensions but isolating China," Mr Carter said.
In the run up to the Hague ruling, senior officials and diplomats from China and the US have criss-crossed the region to drum up support for their position, including with Association of South-east Asian Nations states like Cambodia, Brunei and Laos - which holds the Asean chair this year.
China has separately embarked on a media and public relations campaign, with its ambassadors from the UK to Sierra Leone penning articles explaining its position, alongside paid supplements like one published in the Saturday edition of the Telegraph newspaper in the UK.
China's trade with Asean dwarfs other countries and it has been promoting infrastructure investment in the region to back its military sway with economic clout.
Mr Carter for his part used his speech to tout US ties with allies Japan, Australia and the Philippines, as well as deepening relations with Singapore and Vietnam, where President Barack Obama lifted a four-decade ban on lethal weapons last month.
Mr Carter said he and India's Defence Minister Manohar Parrikar would find new ways to cooperate before Prime Minister Narendra Modi visits Washington next week.
"The United States welcomes and encourages these burgeoning partnerships among like-minded partners who share our vision of a principled regional order," he said.
Mr Carter said that in September, the US and Laos would co-host an informal defense ministers' meeting in Hawaii. That comes after Mr Obama held a summit with Asean leaders in the US in February.
Though Mr Carter expounded on the strength of US relationships in Asia, he did not outline the risks to them, said Euan Graham, director of the international security program at the Lowy Institute for International Policy in Sydney. Incoming Philippine President Rodrigo Duterte has spoken of the possibility of closer ties with China.
"The wild card that really is front and centre now is this shift in the administration in key treaty allies among the South-east Asian countries and among the South-east Asian claimant states, which is the Philippines," Mr Graham said.
Mr Carter repeated that the US welcomes China's rise. "We know China's inclusion makes for a stronger network and a more stable, secure, and prosperous region," he said. "In all of our interactions with our Chinese counterparts, the United States consistently encourages China to take actions that uphold -- and do not undercut -- the shared principles that have served so many in Asia-Pacific so well."
The US wants to work with China on regional security, Mr Carter said. "By networking security together, the United States, China, and all others in the region can continue to ensure stability and prosperity in a dynamic region."
Even so, he warned the US would continue to "fly, sail, and operate wherever international law allows," and called on China to play by international rules. The coming Hague ruling will be a chance for China to lower tensions in the area, Mr Carter said.
China is taking part again in the US-led Rim of the Pacific Exercise this year. Mr Carter said the US and China will sail together from Guam to Hawaii for RIMPAC, conducting seven drills along the way, including one focused on search and rescue.
"I plan, at President Xi's invitation, to discuss this deeper cooperation as well as the concerns I've outlined here, when I travel to Beijing later this year," he said. "America wants to expand military-to-military agreements with China to focus not only on risk reduction, but also on practical cooperation."