Comment by LYK-love

The research competition is basically a funding competition nowadays. In the 20th century, China had far less research funding for universities compared to U.S.. That's due to two facts: 1. China was poor back then. 2. China had barely no high-tech industries which can provide additional financial support to labs and cultivate talents.

Therefore, people got high-level education who want to pursue a research career would have less chance to get a job in China (at least mainland) and had to go to U.S., EU or Japan to utilize their knowledge.

In fact, until now, U.S. still offers the highest the research funding to its universities. That's why there're so many Chinese students in U.S. schools.