- Technology Marches On: 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.
- Actor Allusion:
- Backed by the Pentagon: The CIA scenes were filmed at the actual CIA headquarters; this was the first time the CIA had ever done such a thing.
- The Danza:
- Disowned Adaptation: 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.
- Fake Irish: Only three actors in Patriot Games 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).
- Missing Trailer Scene: The line "There's never been a terrorist attack on American soil" was included in trailers for movie, but was left out of theatrical release because it sounded too much like an invitation or dare.
- Old Shame: Alun Armstrong is said to be embarrassed by his involvement with the film.
- The Other Darrin:
- Harrison Ford takes over the role of Jack Ryan from Alec Baldwin. Ford had been considered to play Ryan in The Hunt for Red October, but declined because he felt the film focused more on Ramius than Ryan.
- Anne Archer replaces Gates McFadden as Cathy Ryan, due to her commitment to Star Trek: The Next Generation.
- The only returning castmember is James Earl Jones.
- Shout-Out: One of the villains 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.
- What Could Have Been:
- 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.
- Pete Postlethwaite was offered the role of Owens but he was working on another American film at the time.
- Alec Baldwin was offered the role of Jack Ryan again, but decided to do a play instead.
- Sylvester McCoy was considered for the role of Cooley.