Reading "Clear and Present Danger" is an interesting experience. I've seen the film, of course, which I thought was okay but not great. However, as far as I can tell, the novel isn't about Jack Ryan - when making the film, they repurposed it to star Harrison Ford. (Interestingly, I think they did the same with "The Sum of All Fears", despite that not starring Harrison Ford. Why not just cast Ben Affleck as the character who was the actual protagonist of the novel?)
However, that's not the 'interesting' part.
What I'm finding interesting is that Clancy is very obviously a real expert in his subject matter. He clearly knows boats, and the operations of the US Coast Guard, and the nature of military life, and something of politics. There's very definitely an authority to his writing; he knows whereof he speaks.
Unfortunately, it seems that what he doesn't know is how to write.
His characters are all given long and detailed backstories... and very little by way of distinct characteristics. They tend to be defined by their jobs, and all tend to be one-of-a-kind individuals who are near-legendary in their fields. And, curiously, they all seem to have a "beautiful young wife", possibly a couple of lovely children, plus (and this is important) a selection of mistresses. Because that's an important detail - I presume that later in the novel two characters will have a conversation about their respective mistresses. (Perhaps trading them like football stickers - "got, got, need, doubler, got...")
Likewise, his descriptions of mundane events are full of all sorts of fabulous details about how things work, and how the organisations operate. Fantastic. Except that it slows the pace down to a crawl. Oh, and also, when something actually does happen, the details tend to be glossed over rather quickly - presumably because at that point he doesn't know whereof he speaks, and so can't write with the same authority.
It's frustrating - I think there is quite an entertaining story under there, once I wade through all the extraneous detail. But then, it's quite likely that this is one of those cases where the film really is better than the book.