Wal-Mart and other big-box discount retailers such as Target or Home Depot have been vilified as selfish retailers that mistreat their workers, outsource American jobs, uproot communities, and harm the poor. Others, however, argue that these stories have improved Americans' standard of living, especially among the less affluent. Which of these competing visions is correct? Is Wal-Mart a ford for good or evil? Is it a saint of a sinner? In the Wal-Mart...