First of all, I'm not a Tom Clancy fan, only because for whatever reason I've never gotten around to reading any of his books. I would say it's because so many of them are so huge, but I've always been a voracious reader. I've read almost all of Stephen King's novels, which are also pretty huge, and I'm usually reading three or four at a time. At any rate, I have nothing to offer as far as how closely the movie follows the source material, although I really think this is incredibly important when adapting books to movies.
I have read a lot of criticisms of Patriot Games (and even more of the sequel, Clear and Present Danger), and while I agree with mostly all of it, I still think Patriot Games is a good couple hours of good clean cinematic fun. But maybe that's just because I love Harrison Ford.
Ebert makes the obvious complaint that Jack Ryan, when he finds himself in danger, sends his family to a remote cabin rather than a secure bunker at CIA headquarters, and it's true that this detracts from the movie, but you have to have a movie somehow, and that's a situation where making the smart, real life decision would cancel out the rest of the movie. If everyone in movies made the smart decision all the time, we wouldn't even have a horror genre, for example.
Jack Ryan is described in Clancy's novels as having "undistinguished features," which makes Harrison Ford seem to me like the perfect choice to play him, since I've always thought that, even though he's a brilliant and tremendously loved actor, he can't really act with his face very well. Consider one of my favorite examples of this, the close up shot of his face when he sends that kid into surgery in The Fugitive. You can literally see the effort he's putting into making his face do something moving, and it's just not happening. But the thing it, the shot still works. I don't get it, it's a mystery, as Philip Henslowe might say.
Harrison Ford has played more complex characters (and less complex, of course), and Jack Ryan gets better than this, but Patriot Games is a fun introduction of Ford playing the role, and is especially a must see for Clancy fans.
