!!The novel

* TechnologyMarchesOn: The British police investigating the attack on the royals are quite impressed by Jack's "Cambridge Datamaster Model-C Field Computer", which has ''two megabytes'' of memory. Well, it ''is'' pretty impressive for 1983.

!!The film

* ActorAllusion:
** Jack Ryan (Harrison Ford) is seen crossing Hanover Street. ''Hanover Street'' is the title of another novel made into a movie starring Harrison Ford.
** The scene in which Ryan zooms in on and analyses different parts of the satellite photograph is a ShoutOut to ''Film/BladeRunner''.
* TheDanza: Sean Bean as Sean Miller.
** A surname example: Samuel L. Jackson as Robbie Jackson.
* DisownedAdaptation: Tom Clancy was very unhappy with the numerous changes the film made from the original novel. He also felt that the 49-year-old Harrison Ford was too old to play the 31-year-old Jack Ryan.
* FakeIrish: Only three actors in ''Film/PatriotGames'' were actually Irish: Richard Harris, Patrick Bergin and Jonathan Ryan. This means all of the other Irish characters were this. Englishwoman Polly Walker plays the IRA terrorist Annette, though it is revealed in film that Annette is British-born (presumably of Irish ancestry).
* TheOtherDarrin: HarrisonFord takes over the role of Jack Ryan from Alec Baldwin. Ford had been considered to play Ryan in ''Film/TheHuntForRedOctober'' before Baldwin was cast.
* PlaneSpotting: A pair of [[EveryHelicopterIsAHuey Hueys]] appear during the SAS raid ([[JustPlaneWrong despite the Brits never flying Hueys]]). The Libyan camp scenes feature what appear to be the much more rarely seen Sikorski H-34s.
* ShoutOut: One of the villains [[spoiler: while waiting for his assassin]] is watching ''Harry's Game'', a miniseries about a British Army officer undercover in the IRA. The main score can be heard in the background during the scene.
* WhatCouldHaveBeen: The final battle was originally supposed to have Ryan and Miller fighting on large rocks in the middle of the stormy sea. The fight would end with Miller drowning. Test audiences weren't excited with this conclusion, so the final battle was changed to a boat chase instead.
** Alec Baldwin was offered the role of Jack Ryan again, but decided to do a play instead.