For what it's worth, I'm not a picky movie viewer. I'll watch nearly anything. So for me to complain about this movie means that something was really off-base.
As far as an action movie goes, it was passable. As far as the technological thriller that the book was, it doesn't even come close. There is no character development (never felt anything towards Ding), random changes in a character's persona (Clark goes from wanting to kill Ryan to making the chopper go back), thing missing that are important to the plot (downing of drug running planes), and things that were never in the book (yacht owner tied to the President).
To make what could be an extremely long review somewhat shorter, if you've read the book and are a fan of Tom Clancy, don't bother. If you're just looking for a film with " 'splosions," this might work.