THE BEST AND THE BRIGHTEST
by DAVID HALBERSTAM
688 pages. Random House. $10.
Like Viet Nam itself, The Best and the Brightest starts with a thread and leads into a labyrinth. The beginning is the simple question: "Why, why had it happened?" Before David (The Making of a Quagmire) Halberstam, one of the pre-eminent war correspondents of that undeclared war, can contain his question, he is deep in his own maze, wrestling with his own minotaur. It is an awesomely pretentious and yet unavoidable monster, which he describes as "a book about America, and...