Robotic Sub
One of his more enjoyable books. The premise is interesting: a robotic sub hijacked by its' creator and turned on the U.S. It also wraps up the conflict between Michael Pacino and his old nemesis.
New characters are introduced, including Pacino's son, Anthony, who is grown up now, and training to be a submarine officer. Even his first dive is beautiful. "Dive, dive...decks awash...sail's under...scope's awash...scope's under." I could almost see the phosphorescent foam and the underside of the waves before the sea turned to black.
Of course, his recurring theme of inevitable sexual encounters when female submariners are aboard continues.
One concept he deals with well, is the struggle in Anthony's mind when his sub is torpedoed while he is diving outside the hatch at periscope depth. As he considers the lifetime consequences of survival vs. patriotism, he realizes his survival guilt would not be worth it, and he returns to the stricken sub with his shipmates.