Read a bit more economics will help you analyze China's economy.
If either the US imposes a sanction on Chinese export or China stops exporting, China will be better off in the long run. This is because China has to encourage domestic consumption, this will make China's GDP much more balanced and the economy more competitive. This is the long term effect, but in the short-run the economy will suffer.
If you dont believe and you have access to The Economist magazine, go and search those articles about China's economy, this will give you much better idea.
In a recent article published in Caijing (the term in Mandarin means finance), Wu Jinglian, an economist at the Development Research Centre of the State Council, writes, While Chinas economic growth continues to accelerate, fundamental problems such as resource consumption, environmental degradation, economic inequity, political corruption and the widening gap between the rich and the poor are becoming increasingly acute and attracting criticism from the public. Large parts of China are experiencing acute water shortage. In spite of the tremendous developments all around China, its political leadership considers food and water security to be its highest priority. As and when it becomes necessary, and it may already be so, China will start diverting major rivers and glacier melts for its own use, without the slightest concern about the consequences for its neighbouring countries.
There are other ideological issues that continue to trouble China. In the same article in Caijing, Wu Jinglian writes that at the end of 2003 the voice of the old guard was suddenly heard, which declared that eliminating the planned economy and instituting marketization are equivalent to changing the socialist system and adapting capitalism. It went on to put the blame for Chinas social problems on reform and on the opening up of its economy. In 2006, it even began publicly calling for the posthumous rehabilitation of the Gang of Four, the continuation of the revolutionary line under the dictatorship of the proletariat and a restart of the Cultural Revolution.
Such moves after thirty years of reforms were strongly countered at the 17th National Congress of the Communist Party of China, where the general secretary, Hu Jintao, unequivocally reaffirmed the success of the reforms and the opening up before the cultural committee of the CPC. His rebuttal declared that reforms brought about Chinas transformation from a highly centralized planned economy to a robustly socialist market economy. He went on to say that reforms and opening up are the only ways of developing socialism with Chinese characteristics and of rejuvenating the Chinese nation. All this shows that arguments regarding reforms continue to simmer within China and, to an extent, explain its belligerent attitude to any criticism or dissent.