I don’t know why the idea that communists would go to great lengths to fell the US would be at all viewed as a “fantasy” or a “conspiracy theory.”
Especially when they will tell you, if you bother to ask them.
They have been screaming this at us for decades.
The only fantasy is the one that most Americans are living daily. They believe America is all-powerful, infallible and evergreen. They will laugh at you if dare try to explain that the hard left has infiltrated every level of our government as part of a bigger plan to destroy the American way of life.
The notion that communism is not a threat is the real fantasy, perhaps a fatal one.
Not sure what your point is, because I'm saying it's NOT a fantasy.