1945 to 1975. What are the reasons and effects of China's immigration to the United States?

At that time, the domestic society was in turmoil, and even after the founding of New China, the political struggle was cruel, and many capitalists were treated unfairly. Furthermore, at that time, China's economy was backward, and its living standard and living environment were not satisfactory. In order to pursue a better life, many upper-middle class people immigrated to the United States.