Yeah, I think the archetypal example of the US imperialist writing sci-fi is Cordwainer Smith (a cheeky pseudonym). He was a literal spook, working for the OSS and CIA after, then the State Dept. He hated the hippie movement in the US However, like a lot of fash authors, his works inspired some great stuff. Cordwainer Smith has been cited as an inspiration for Akira, Ghost in the Shell, and Evangelion.

but if it's just licensed sci-fi paperback shit like mass effect or star wars or whatever, i don't think there's anything other than its on-the-face entertainment value there

edit: some choice quotes from Smith's wiki page (real name Paul Myron Anthony Linebarger)

he was sent to China to coordinate military intelligence operations. When he later pursued his interest in China, Linebarger became a close confidant of Chiang Kai-shek.

He was recalled to advise the British forces in the Malayan Emergency and the U.S. Eighth Army in the Korean War. While he was known to call himself a "visitor to small wars", he refrained from becoming involved in the Vietnam War, but is known to have done work for the Central Intelligence Agency. In 1969 CIA officer Miles Copeland Jr. wrote that Linebarger was "perhaps the leader practitioner of 'black' and 'gray' propaganda in the Western world".[5][6] According to Joseph Burkholder Smith, a former CIA operative, he conducted classes in psychological warfare for CIA agents at his home in Washington under cover of his position at the School of Advanced International Studies.

He used his experiences in the war to write the book Psychological Warfare (1948), regarded by many in the field as a classic text.