Between 1947-1956 the FBI included "It's a Wonderful Life" on a secret list of films suspected of being Communist propaganda. Oddly, there is also a Ayn Rand connection.
From Federal Bureau of Investigation, file no. 100-HQ-138754 via Aphelis.net...
“IT’S A WONDERFUL LIFE”
Released by RKO Pictures, Inc. on December 19, 1946
Producer — Frank CapraDirector — Frank Capra
Screen play — Frances Goodrick, Albert Hackett, Frank Capra
Cast: Starring — James Stewart, Donna Reed, Lionel Barrymore
According to the Informants [REDACTED] in this picture the screen credits again fail to reflect the Communist support given to the screen writer. According to [REDACTED] the writers Frances Goodrick and Albert Hackett were very close to known Communists and on one occasion in the recent past while these two writers were doing a picture for Metro-Goldwyn-Mayer, Goodrick and Hackett practically lived with known Communists as Lester Cole, screen writer, and Earl Robinson, screen writer. Both of these individuals are identified in Section I of this memorandum as Communists.
With regard to the picture “It’s A Wonderful Life”, [REDACTED] stated in substance that the film represented a rather obvious attempt to discredit bankers by casting Lionel Barrymore as “scrooge-type” so that he would be the most hated man in the picture. This, according to these sources, is a common trick used by Communists.