The US also tried internationalizing the maritime disputes by urging ASEAN to form a united front to negotiate with China and inviting Japan, India, Australia, and even the European Union to "help stabilize" the situation in South China Sea.

In the economic arena, Obama administration put forward an ambitious trade vision for the Asia-Pacific centered on US and based on US preference for "high standard, 21st century" free trade agreement, preventing China's economic influences and dislodging China's free trade vision in Asia.

In cyber security, the US tried imposing its version of rules of the road. In a word, both the US and China are a little bit disillusioned with the either side.

So the logical questions to ask is: What can Xi Jinping and Obama do during the summit to offset this downturn trend in China-US relations? And what can be expected of China-US relations in general?

While it's unrealistic to expect China-US relations to solve all the problems, or even clear the distrust between them, it is quite possible that China and US can forge some kind of "we can do" working relationship. Luckily, despite mounting differences and distrust, there're also increasing common interests for cooperation, from climate change to combating global epidemics, from piracy on high seas to preventing WMD proliferation, from combating terrorism and religious extremism to preventing global financial crisis, from promoting world economic growth to reducing poverty.

China's successful story of more than thirty years of fast economic growth benefits greatly from the stable and friendly environment it has enjoyed since its opening up to the outside world in 1978. Without a stable environment, integrating itself into the world economic system, China could not have achieved what it has achieved in the past thirty years. The US has also benefited a lot from the economic miracle in East Asia, and has expanded its export market and sharpened its economic competitiveness.