The premise of this 18th book by the host of PBS' "News Hour" is that a fifty year old men's clothing salesman buys a Vietnam era Marine's Silver Star medal on eBay and is transformed, by wearing the accompanying lapel pin, into a heroic figure. Haunted by the knowledge that the respect he is given by those who recognize the pin is undeserved, he attempts to become the Marine that he is assumed to be. The Phony Marine studies the Marine Corps, learns to swear, diets, exercises and shaves his head in order to play the part.
Accident, or deus ex Microsoft, places him in a couple of confrontations where he has to act the hero, he is made much of in the local, Washington DC news and is awarded another medal by the city of Washington. He tries to get himself transferred to
another store in Dallas, so that he can escape his past associations and his ex-wife, the better to be the new him, but is met there by a store employee who is a real Marine and decorated hero. Eventually the salesman confesses his masquerade to the people that he has fooled and throws the medal and it's ribbons and pin into the Potomac, but is accepted as a hero anyway, by some of them, because of his heroic actions at the beginning of this paragraph.
Lehrer, by the way was an infantry officer in the Marines in the 1950s. I guess he can get away with making this Jiminy Cricket, you are what you think you are, transformation in his character, where I wouldn't have dared. My nose would have grown far too long.