The summit had all the qualities of a meeting between great friends and allies – long talks spread across two days, a lively dinner with both parties bringing drinks and even a moment where the two leaders slipped their handlers for nearly an hour to stroll outside and chat on their own.
The talks between Barack Obama and Xi Jinping over eight hours on Friday and Saturday weren’t just unusual for their setting, the Sunnylands resort in Palm Springs, where the streets are named after the likes of Frank Sinatra and Bob Hope.
The breadth of the talks and their timing, at the start of their second and first terms respectively, were “unique” in Sino-US meetings since the two countries opened a dialogue in 1971, said Tom Donilon, Mr Obama’s outgoing National Security Adviser.
What is less clear, and may not be for years, is whether the summit will mark a reset in a distrustful relationship between an established power and a rising rival, with all the dangers that entails.
“China and the United States must find a new path, one that is different from the inevitable confrontation and conflict between the major countries of the past,” Mr Xi said bluntly.
The perennials of such summits, such as human rights and, more recently, Washington’s charge that Beijing was unfairly rigging its currency to boost exports, were low on the list at Sunnylands.
Whereas US leaders might once have handed over the names of jailed dissidents to their Chinese counterparts, Mr Obama provided the “specifics” of what Mr Donilon called “cyber-enabled economic theft” by Chinese entities from the US government and private businesses.
Mr Xi, on the opening day, sounded dismissive of US complaints, suggesting many media reports had wrongly implied that cyber was the most important bilateral issue.
Mr Donilon, in a briefing at the summit’s close, could not have been clearer in sending the opposite message, saying: “The president underscored that resolving this issue is really key to the future of US-China economic relations.”
“It is now at the centre of the relationship,” he said, adding that if the Chinese leadership did not understand before the seriousness of cyber for the US, they did now.
Yang Jiechi, Mr Xi’s chief foreign policy adviser, played down complaints about cyber theft in comments to reporters, and did not acknowledge Chinese state involvement in attacks.
“Cybersecurity should not become the root cause of mutual suspicion and frictions between our two countries. Rather, it should be a new bright spot in our co-operation,” he said.
Awkwardly, Mr Obama stressed that the issue of cyber theft was separate from the parallel controversy about US domestic intelligence agencies hoovering up of data from local phone and Internet companies.
Mr Donilon also highlighted what he called renewed co-operation between the US and China to prevent North Korea from entrenching and expanding its nuclear program, without giving details.
“A recognised nuclear weapon state in Pyongyang would have profound implications in the rest of northeast Asia, and these are obviously results that the Chinese don’t want to see,” he said.
On the Chinese side, Mr Xi staked out Beijing’s own territory, saying that the “vast Pacific Ocean” was big enough to accommodate both powers.
Mr Xi’s statement underlined China’s push to get the US to acknowledge Beijing’s sovereign interests in the region, or at the very least, stay out of its disputes with neighbours over the South China sea.
Mr Xi “reaffirmed that China is determined to safeguard national sovereignty and territorial integrity” while solving problems “through dialogue,” Xinhua, the state news agency, reported.
Far from staying out of such clashes, the US under Mr Obama has pressed its interests in the region, on issues such as territorial disputes in the South China sea.
But US allies in Asia, especially Japan, nonetheless viewed the summit with anxiety, worried closer ties between Washington and Beijing could be at their expense.
Mr Donilon said US allies expected America not just to meet its obligations as an ally, but also have “a productive and constructive relationship with China”.
The two sides agreed to start regular military-to-military talks, something the US has long pressed and also to work together to phase out hydrofluorocarbons, greenhouse gases used in fridges and air conditioners.
Henry Kissinger, whose secret trip to China in 1971 opened modern Sino-US relations, said both sides needed to be serious about the dialogue, because of the dangers of it failing.
“If it works well and both sides are lucky, then at the end of 10 years, this may have become a habit that has transformed international relations,” he told CNN. “If it doesn’t work, each side will look after its own interests. We surely will.”
When the two leaders went for their stroll, with interpreters, on Sunday morning, they sat down on a bench made specially for the occasion from Californian redwood.
A gift from the US, the bench returned with Mr Xi’s delegation to China. Mr Xi has invited Mr Obama to a similarly informal summit in China at, as of yet, a location unknown.
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