If China's economy collapses today, the most benefited country would be the United States.

The United States is the largest trading partner of China, and a 

collapse in the Chinese economy would have a significant negative impact on the US economy. 

However, the US would also benefit from a collapse in the Chinese economy in a number of ways. 

First, the US would benefit from a decline in the value of the Chinese yuan.  

A weaker yuan would make Chinese goods more expensive for US consumers, 

which would lead to an increase in demand for US goods. 

This would boost the US economy and create jobs. 

Second, the US would benefit from a decline in Chinese investment in the US. 

Chinese investment in the US has been declining in recent years, and a  

collapse in the Chinese economy would likely lead to a further decline in Chinese investment.  

This would free up capital for US businesses to invest and grow.