He achieved recognition as one of America's leading experts in rockets and high-speed flight theory prior to his returning to China in 1955.

Afterward, he joined Theodore von Kármán's group at the California Institute of Technology in 1936, received a doctorate in aeronautics and mathematics there in 1939, and became an associate professor at Caltech in 1943.

[1][4] He was given a deferred deportation order by the Immigration and Naturalization Service, and for the following five years, he and his family were subjected to partial house arrest and government surveillance in an effort to gradually make his technical knowledge obsolete.

[1] After spending five years under house arrest,[5] he was released in 1955 in exchange for the repatriation of American pilots who had been captured during the Korean War.

He also played a significant part in the construction and development of China's defense industry, higher education and research system, rocket force, and a key technology university.

After graduating from college, Qian was admitted to the Boxer Indemnity Scholarship program, enabling him to study in the United States.

Theodore von Kármán, Qian's doctoral advisor, described their first meeting: One day in 1936, he came to me for advice on further graduate studies.

I was immediately impressed with the keenness and quickness of his mind, and I suggested that he enroll at Caltech for advanced study ... Tsien agreed.

I found him to be quite imaginative, with a mathematical aptitude that he combined successfully with a great ability to visualize accurately the physical picture of natural phenomena.

Shortly after arriving at the California Institute of Technology in 1936, Qian became fascinated with the rocketry ideas of Frank Malina, other students of von Kármán, and their associates, including Jack Parsons.

[27][28] Von Kármán wrote of Qian, "At the age of 36, he was an undisputed genius whose work was providing an enormous impetus to advances in high-speed aerodynamics and jet propulsion.

[35] By the early 1940s, U.S. Army Intelligence was already aware of allegations that Qian was a communist, but his security clearance was not suspended until prior to the Korean War.

Despite support from his colleagues and no proof of the allegations, he received a deferred deportation order from the Immigration and Naturalization Service, and for the following five years, he and his family were subjected to partial house arrest and government surveillance intended to undermine his technical expertise.

[40] Qian was taken into custody on September 6, 1950, for questioning [6] and for two weeks was detained at Terminal Island, a low-security United States federal prison near the ports of Los Angeles and Long Beach.

[41] In August, Qian spoke with Dan A. Kimball, the United States Under Secretary of the Navy at the time, whom he knew personally.

[42] Kimball, determined to help, referred Qian to a lawyer in Washington, DC, to assist him in having his security clearance restored.

[44] Qian stated that all classified documents were locked in a cabinet in his office, and he gave the keys to a colleague, Clark Blanchard Millikan.

[46] They further explained that the technical papers in Qian's collection were either outdated or authored by him, and that all the documents he had were characteristic of those held by top experts in the fields of aircraft and missile design.

[46] On April 26, 1951, Qian was declared subject to deportation and forbidden from leaving Los Angeles County without permission, effectively placing him under house arrest.

Evidently, Qian's approach is primarily practical, as Krendel notes that for servomechanisms, the "usual linear design criterion of stability is inadequate and other criteria arising from the physics of the problem must be used."

With Dwight Eisenhower agreeing, Qian departed from Los Angeles for Hong Kong aboard the SS President Cleveland in September 1955 amidst rumors that his release was a swap for 11 U.S. airmen held captive by communist China since the end of the Korean War.

"[4] Upon his return, Qian began a successful career in rocket science, boosted by the reputation he garnered for his past achievements as well as Chinese state support for his nuclear research.

In October 1956, Qian became the director of the Fifth Academy of the Ministry of National Defense, tasked with ballistic missile and nuclear weapons development.

Qian's reputation as a prominent scientist who was caught up in the Red Scare in the United States gave him considerable influence during the Mao era and afterward.

[52] In 1989, after the Tiananmen massacre, he denounced the demonstrators as 'evil elements' and, in line with prevailing orthodoxy, branded the dissident astrophysicist Fang Lizhi 'the scum of the nation'.

In 1969, Qian was one of a group of scientists who spoke with Australian journalist Francis James, describing China's first seven nuclear tests and details of a gaseous diffusion plant near Lanzhou.

From the 1980s onward, Qian had advocated the scientific investigation of traditional Chinese medicine, qigong, and the pseudoscientific concept of "special human body functions".

Qian eventually received his award from Caltech, and with the help of his friend Frank Marble, brought it to his home in a widely covered ceremony.

He was gifted with a golden mind in mathematics and displayed multiple talents at young age – such as memorizing hundred of poems when he was three – and was good at music and painting when growing up.

These narratives create a near-miraculous Qian, with a strong impression that he was not only a missile expert, but an all-rounder; not only a scientific giant, but a built-in communist revolutionary.