Disowned Adaptation: Tom Clancy was very critical of the film adaptation of Clear and Present Danger. Most notably, he disliked the ending. In the movie, Ryan blows the lid off the covert operation in Colombia by publicly testifying before Congress. In the book, the men responsible for the operation are quietly dealt with behind the scenes. Tom Clancy feels that Jack Ryan would never take a course of action that would result in the United States being damaged by a major scandal.
Fake American: British-born actor Donald Moffat as President Bennett.
Stock Footage: Footage shot for this film, featuring the F-18 Hornet, was used for 10 seasons in the opening titles on the Creator/Paramount series JAG. Footage from the convoy ambush scene was also used by JAG, in the first season episode "War Cries" (with careful editing to remove Harrison Ford in a suit and insert David James Elliot in Navy Whites).
Throw It In: Ryan's line asking Ritter if he played tennis (to distract him during the computer showdown) was ad-libbed by Harrison Ford.
A subplot involving Cathy Ryan performing experimental eye surgery on a child was filmed, but cut from the final film.
The first draft of the script was written by John Milius, and allegedly it was faithful enough to the book that Tom Clancy loved it. This script was ultimately discarded because, just like in the book, Jack Ryan barely appears in the first half of the story (instead the first half of the story is mainly about John Clark and the American soldiers in Columbia) and the studio wanted Jack Ryan to be at the center of the story (they feared that if Jack Ryan's role wasn't big enough, Harrison Ford would not agree to star).