This genre of novel (sort of military thriller fiction) is not usual for me and this is the first Clancy book I have read. That being said, the book has been on my "to-read" list for a fair amount of time and so I am glad I got round to reading it.
I also hadn't seen the movie (starring Sean Connery and Alec Baldwin) by the time I read it and so I didn't have any pre-perceived ideas about the story and could read afresh.
Side note: I have now since watched the movie, and whilst the core plot is mostly the same there are a lot of differing details throughout (in terms of both angle and storyline), and so I can certainly recommend both media if you've previously seen one or the other or neither.
In general, I very much enjoyed the book. It was an exciting read from start to finish, with interesting characters, relationships and story arcs. I was fascinated by all of the technical detail and also felt that it helped explain and justify many of the core concepts and features of the story. The character development was good, and you quickly build a connection with many of the different people involved.
Though I do not think this a fault of the author (I imagine the work is an accurate reflection given the time of the setting), I would hope that if it were written in modern times there would be improved gender diversity and more female representation in the novel - as it is I do not remember there being a single female character (aside from mentioning wives and family members who do not appear in the story directly).
Either way, I can certainly recommend the book to others who also enjoy an exciting story and lots of technical detail. I thought the run-up to the ending was great and I am definitely intrigued to further my reading in this genre.