Clear and Present Danger is the fifth (blurb) or fourth (SYKM) in the Jack Ryan series by Tom Clancy. It has dropped to $1.99 at Kindle and Kobo US. As I've mentioned before, I don't like the way Clancy's politics really obviously bled into his later books (or even, IMO, overwhelmed some of them), but he did write some good thrillers early on, like
Red Storm Rising and
Hunt for Red October. Up to you to decide

if you think this is one of them!
Kindle US:
https://www.amazon.com/Clear-Present...dp/B001QEAQQ2/
Kobo US:
https://www.kobo.com/us/en/ebook/cle...esent-danger-1