I very much regret that Tom Clancy has entered partnership with a number of other writers where the other author does the writing but the end product is published as a Tom Clancy's book. Jeff Rowan writes in a style comparable to Clancy's but Jerome Preisler, the writer of Zero Hour, has a style which is, in my view,far more suited to an old fashioned novel than to a thriller or action story.
There is nothing technically wrong with this book but it is far too slow moving and spends far too much time describing matters which are not relevant to the story. It is one of only a very small number of books that I have put away without finishing it. I think that Tom Clancy does us, his readers a disservice by publishing books like this under his own imprimatur.