China is the leading trading partner of the US today. Nearly $747 billion worth of goods and services exchanged between each other. This statistics is based from the Office of the United States Trade Representative.
The exports from China is about $550 billion worth of goods. However, it is only $179 billion from the US. So, this is seen as a trade imbalance as US imports more from China. Now, the US is imposing more tariffs against goods imported from China to counter this trade imbalance, leading to a trade war.
But winning a trade war is only possible when there are no retaliatory tariffs. So, China could liquidate over $3 trillion in dollar denominated reserves, which can cause a serious damage to the system. US companies need Chinese products and services to keep the manufacturing costs low to profit from consumers.
Causing a damage to the economy of the trader partner will also cause a damage to the economy of the country that does the trade war. Many leading US companies including the defense sector is dependent on raw materials from China. So, trade war is not a solution, but can only worsen the situation. The solution is negotiations between the two trade partners to correct the trade imbalance.