At first, Pfarrer's tough-guy bravado can be off-putting. But after a few chapters, you get caught up in his riveting transformation from ''pooka-shell-wearing surf dude'' to Navy SEAL commando. His 1983 peacekeeping tour in Lebanon offers a fascinating perspective on the frustrations and ultimate futility of a conflict that, in one day alone, resulted in the deaths of 243 soldiers. (''To this day I have no goddamn idea what the United States of America was doing in Lebanon.'') Pfarrer visits other '80s hot spots: A showdown in Sicily with the Achille Lauro hijackers and an amphibious confrontation with a Nicaraguan patrol boat prove especially memorable. Even so, the writing sometimes sounds like a B movie (not surprising from the screenwriter for 1997's The Jackal), and civilians should be prepared for frequent trips to the book's military glossary.