Have China-U.S. relations become more constructive or have they deteriorated? As the year comes to its end, the question haunts everyone who follows the interactions of the world's top two economies. 

In brief, China-U.S. relations have maintained stable in 2015, but are visibly complicated. In retrospect, bilateral relations can be generally divided into three phases: 

In the first half of the year, despite the fact that the two governments had announced Chinese President Xi Jinping's state visit to the United States seven months earlier, it did not prevent controversial issues from coming to a boil. The Obama administration attempted to thwart the creation of the China-led Asian Infrastructure Investment Bank (AIIB) due to heavy skepticism about China's intentions, and in the meantime gave full support to Japan lifting the ban on its right to collective self-defense. The voices in America advocating the "containment of China" rose in number and in volume.  

From June to October, in spite of their sharp disagreements, China and the United States carried out intensive interaction and coordinated their interests. In September, President Xi paid his first state visit to the United States since coming to office, which was seen as a success both at home and abroad. The mutual wish for cooperation and conciliation was sincere.  

Then in the last three months, the two countries forged ahead implementing agreements achieved during President Xi's visit. They reached consensus on a range of important issues including trade and cybersecurity, as well as making progress in global affairs, such as redoubling their commitments to combating climate change ahead of the Paris conference. However, sensitive issues concerning the South China Sea, human rights, and Taiwan are still prominent in the relationship with sharp divergence between the two nations. On December 16, the Obama administration authorized a $1.83 billion weapons sale to Taiwan despite strong opposition from the Chinese Government. Beijing then announced sanctions on the companies involved in the arms sale. It is a pity that the China-U.S. relationship in 2015 has to end like this.  

Indeed, the scope of China-U.S. cooperation has extended to a global level. However, the risk of strategic collision of the two countries is on the rise, while bilateral competition for the upper hand in writing international rules is clear. 

At the same time, the influence of domestic politics on China-U.S. relations is increasingly transparent. The interest groups that have an impact on the direction of the relationship are pulling the two in opposite direction, with the number of obstacles increasing.  

Against this backdrop, the furthering of China-U.S. relations requires more than traditional diplomatic solutions. 

In spite of palpable tensions, the strategic goals of the two countries are not fundamentally opposed, but somewhat parallel with one another: They have no intention to dominate each other, and aiming for interdependence and mutually beneficial cooperation is still their best policy choice. 

The year 2016 will witness the regional leadership election in Taiwan as well as the U.S. presidential election, meaning the bilateral relationship will endure more tests. When the new U.S. president takes power in January 2017, the United States' China policy could dance to another tune. Democrat or Republican, the new resident of the White House is likely to start with a "tough on China" policy in reaction to domestic pressures.  

But the China-U.S. relationship is too important to be defined just by perceived competition. The leaders of both sides need to speed up the development of the relationship into a more mature one that can sidestep the Thucydides Trap with concrete cooperation and newfound trust.  

The author is an op-ed contributor to Beijing Review  and a researcher at the Pangoal Institution

Copyedited by Mara Lee Durrell

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