At the border, two nations colossally unequal in wealth and military strength face each other in a modern version of David and Goliath. Nowhere else in the world does the asymmetry loom greater, as the huge gap in per capita income and production between the two neighbors verifies. The border is an “open wound,” writes Gloria Anzaldua, the Chicana poet, “where the Third World grates against the first and bleeds”; or, in the words of a Mexican, where people fleeing from ubiquitous poverty, the ceaseless search for jobs, and the bane of political thuggery are drawn northward by the mirage of the First World.