I’ve read virtually all of the Clancy novels, and no, they do not go all over the place. They are in chronological order with the exception of Patriot Games:
Red October: Ryan is a CIA analyst, figures out what Red October (Russian missile sub) is up to.
Patriot Games: This one was a prequel. Takes place before Red October. Ryan is a lecturer of naval history. Stops an attack on English Royals and pisses off the IRA. Explains how he came to work for CIA.
Cardinal of the Kremlin: Takes place after Red October. Ryan has to figure a way to save the life of CIA’s top Soviet spy.
Clear and Present Danger: Ryan is now one of CIA’s senior officers. Stumbles into an illegal operation by the CIA targeting drug cartels.
Sum of All Fears: Ryan is now deputy head of CIA and has to deal with a crisis triggered by a nuclear attack on the US by terrorists.
Debt of Honor: Ryan is promoted to National Security Advisor. DEals with an economic and military attack on America.
Executive Orders: Picks up where Debt of Honor lefts off. The assassination of the president gets RYan promoted to El Presidente.
Rainbow Six: Ryan is in the background and is only mentioned once, but he’s still president. Main focus is on the new NATO CounterTerror team.
The chronology of the Jack Ryan books are correct and make sense. The movies screw it up somewhat. And Sum of All Fears…well, let’s just say they chose to forget about Red October, Patriot Games and Clear and Present Danger when they made this movie.
EDIT:
The top operative of R6 is not Ryan’s son-in-law. John Clark is R6’s boss and is Ryan’s friend. Chavez is one of the leaders of the commando teams and is Clark’s son-in-law. Just wanted to clear that up.