The possibly topical case of Laura Ingalls (1893-1967) (not THAT Laura Ingalls, though she was a distant relative and was friendly with Laura’s daughter, Rose Wilder).
THIS Ingalls was a record-setting American aviator and Nazi who was arrested and jailed for failure to register as a paid German agent during World War II. At her trial, the prosecution revealed that her German handler had encouraged her to work with the isolationist America First Committee.

Ingalls gave speeches for the Committee in which she derided America’s “lousy democracy” and gave Nazi salutes. Von Gienanth praised her oratorical skills. She had made a careful study of Mein Kampf, on which she based many of her speeches, as well as pamphlets by Hitler such as My New Order and Germany and the Jewish Question, and Elizabeth Dilling’s books The Roosevelt Red Record and The Octopus. She expected Hitler to win the war; in April 1941, she wrote to a German official, “Some day I will shout my triumph to a great leader and a great people… Heil Hitler!” After the German declaration of war on December 11, 1941, she went straight to Washington to receive a list of contacts from von Gienanth, and was arrested a week later.

She served 20 months.

Prison had not altered her views, however. A few months after her release, she stated her opinion of the Normandy landings:

This whole invasion is a power lust, blood drunk orgy in a war which is unholy and for which the U.S. will be called to terrible accounting… They [the Nazis] fight the common enemy. They fight for independence of Europe—independence from the Jews. Bravo!

She was later arrested trying to cross into Mexico with a stash of Nazi propaganda but was not prosecuted. She applied for pardons after the war but was consistently refused.