Been re-looking at this book which I read a long time ago. I highly recommend at least the first hundred or so pages. It is amazing at conveying not just the facts and story but an attitude, a sensibility. That seems like a trait of the best non-fiction. The articles in LA Weekly, say, often try for this and don't nail it.
The book is about the men, largely Harvard-associated men, who controlled foreign policy as America drifted into the Vietnam War. Many of the characters described are attractive in some ways, brilliant and stylish and confident, but their blind spots and their massive arrogance helped the country slip into tragedy. Much of the book is in the form of mini-profiles: McGeorge Bundy, for instance, who almost became president of Harvard when he was 34.
But it's also a story about how tiny errors, misunderstandings, and biases accumulate into enormous disasters - the French experts at the State Department were considered cooler and more prestigious than the Asia experts, personal status battles kept some people out of key meetings, people had fixations based on their WWII experiences, egos and political debts had to be soothed or paid off with important appointments, on and on.
Anyway, I can't recommend the whole book, which gets pretty detaily, but an interesting thing to flip through at the bookstore or library.