If our so-called national conversation had any health in it, liberals and conservatives would be fighting to claim Jane Jacobs. Here s what she offers conservatives: She takes down the Utopians, those would-be directors of others lives who, handing down their great plans from above, manage to be aloof and superior, yet meddling and bureaucratic. But she doesn t go after their philosophies; she simply assesses their works, the swaths of cities rendered dangerous and barely inhabited by slum clearance and urban renewal.