COL Charlie Beckwith’s “Delta Force”.
It’s not a chest-thumping book. I have a lot of pages dog-eared and sentences underlined, because it talks a lot about training, getting around bureaucratic inertia in organizations, overcoming fear, and just putting your head down and getting things done. It is a great companion to the book, “The Guts to Try”, CSM Vining’s various interviews on YouTube, and the movie Argo.