DON DELILLO HAS BEEN "WEIRDLY PROPHETIC about twenty-first-century America" (The New York Times Book Review). In his earlier novels, he has written about conspiracy theory, the Cold War and global terrorism. Now, in Point Omega, he looks into the mind and heart of a "defense intellectual," one of the men involved in the management of the country's war machine.Richard Elster was a scholar -- an outsider -- when he was called to a meeting with government war planners, asked to apply "ideas and principles to such matters as troop deployment and counterinsurgency."We see Elster at the end of his service. He has retreated to the desert, "somewhere south of nowhere," in search of space and geologic time. There he is joined by a filmmaker, Jim Finley, intent on documenting his experience. Finley wants to persuade Elster to make a one-take film, Elster its single character -- "Just a man and a wall."Weeks later, Elster's daughter Jessica visits -- an...