Why did Qian Xuesen return to China on 1949, but did not return to China until 1955?

Qian Xuesen, a native of Shanghai, 1929 graduated from the middle school attached to Beijing Normal University and then went to Shanghai Jiaotong University to study. 1934 was admitted by the second international student at public expense in Tsinghua University, and went to study in the United States the following summer. Since then, Qian Xuesen has studied and worked in California Institute of Technology and Massachusetts Institute of Technology. Because of his outstanding achievements in aerodynamics and supersonic flight, he became the youngest tenured professor at the age of 36. In the meantime, he visited the missile technology of Nazi Germany with the US Air Force Advisory Group and was awarded the rank of Colonel by the US Air Force. Qian Xuesen had a successful career abroad and lived a comfortable life. However, on the other side of the ocean, the motherland is changing, which always affects his childlike innocence.

1On October 6th, Qian Xuesen, his wife and a dozen China students studying in the United States spent the Mid-Autumn Festival in a street park near California Institute of Technology. They talked excitedly about the great news of the founding of New China and discussed how to return to China to serve as soon as possible. At the end of the following summer, Qian Xuesen loaded his luggage, 800 kilograms of books and notebooks on the American "President Wilson", which was about to sail to Hong Kong, and immediately prepared to take his family back to China by the plane of Canada Pacific Company. However, Qian Xuesen at this time was unreasonably suspected as the producer of * * *. According to the instructions of the Pentagon, the US Customs illegally detained Qian Xuesen's luggage and books, and the Immigration Bureau informed him not to leave the country. An American undersecretary of the Navy even growled: "Qian Xuesen is worth five divisions no matter where he is. I'd rather shoot this guy than let him go home! " For political reasons, they don't want to see a world-class rocket expert with great military value return to the "red" new China. On September 9th, the US Federal Bureau of Investigation arrested Qian Xuesen and put him in a detention center in Termina Island, where he was brutally tortured. Later, due to Qian Xuesen's protest and the help of American friends, the Immigration Bureau had to release him, but he was still under surveillance.

The outrageous obstruction of the American authorities did not lock Qian Xuesen's heart in returning to China. He and his wife Jiang Ying continued to fight in various ways.

After returning to California Institute of Technology, Qian Xuesen devoted himself to the research of engineering cybernetics, and published more than 300,000 words of English "Engineering Cybernetics" from 65,438 to 0954 in the United States. Qian Xuesen conducted this research, on the one hand, to show China people's talent in engineering technology, and on the other hand, to show the American authorities that he has changed the original research direction of jet propulsion, and to eliminate the excuse that they did not allow him to return to China. Mrs Jiang Ying is a singer who was born in China and studied in Germany. She understands her husband's situation and mood very well. At that time, FBI agents often broke into Qian Xuesen's office and residence. In order to prevent accidents, she neglected her major and resolutely stayed at home to do housework in order to take care of her husband and children. In those difficult years, Qian Xuesen always set up three light boxes at home so as to leave for home at any time.

1June, 955, Qian Xuesen got rid of the spy's surveillance. In a letter written on a small cigarette paper to his Belgian relatives, he sent a letter to Chen Shutong, then vice chairman of the National People's Congress Standing Committee (NPCSC), earnestly requesting the production party and government of China to help him return home. This letter was quickly forwarded to Premier Zhou Enlai. In August 1955, 1, China and the United States held ambassadorial talks in Geneva, and discussed the issue of expatriates in the two countries in detail. On the condition of releasing 1 1 American pilot prisoners of war, China demanded that the United States stop obstructing Qian Xuesen and other China students studying in the United States to return home. Under the negotiation of the China administration, the US immigration authorities finally had to agree to release Qian Xuesen.