What works of fiction (written, filmed, or whatever) have there been with a plot involving the following idea: The President of the US, very soon after being elected, discovers–or has it explained to him or her–that in fact the US presidents have no real power, being forced in some way to follow the directions of some secret group or something.
Pretty much every season of 24, particularly season 5.
There’s always this.
In the Preacher series of Vertigo comics, the whole world more or less is secretly run by the Grail, the secret society dating back to the incarnation of Christ. In an attempt to destroy the Saint of Killers- a damned human soul in the office of the Angel of Death- Allfather of the Grail Herr Starr orders the president of the US (transparently to be taken as Bill Clinton, president at the time) to have a nuclear weapon detonated on US soil, and reminds the supposed “Commander in Chief” just who really runs things.
IIRC, in the game Soviet Strike there’s a voiceover scene where the President ( the actor sounded quite like Bill Clinton ) is told not-quite-outright that if he doesn’t do what he’s told he’ll be assassinated. It’s also implied that’s what happened to President Kennedy.
Not quite the same, but this comic plays with the idea of a POTUS finding himself limited by the conventions & expectations of the regime.
Just wanted to add SCP’s take on the Kennedy Assassination’s “Magic Bullet”, which fits the OP’s question.
The Obama Deception.
Also, Bill Hicks did a bit where he talked about the new president being taken into a smokey room and shown a video of the Kennedy assassination from a never before seen angle, and then asked, “any questions?”