China’s Spy Network in America: A People’s War Against an Open House

Qian Xuesen, a Chinese rocket scientist and California Institute of Technology professor, worked on U.S. missile programs during World War II. In the 1950s, he was accused of communist affiliations and potential espionage. The U.S. put him under surveillance and partial house arrest for several years, but never formally prosecuted him for espionage. In 1955, the U.S. let him go back to China as part of a prisoner exchange. He later became a key figure in China’s missile and space programs.