Oath of Fealty - Larry Niven

In the near future, Los Angeles is an all but uninhabitable war zone, racked by crime, violence, pollution and poverty. But above the blighted city, a Utopia has arisen: Todos Santos, a thousand-foot high single-structured city, designed to used state-of-the-art technology to create a completely human-friendly environment, offering its dwellers everything they could want in exchange for their oath of allegiance and their constant surveillance . But there are those who want to see the utopia destroyed, whose answer to tomorrow's best and brightest hope is mindless violence. And they have just entered Todos Santos. . . .