This booklet explores the role of Mexico's interaction with the United States and assesses the impact of geography on shaping the destiny of the Mexican people. Historically the United States has exerted overwhelming influence over the way that Mexico has developed economically. Most importantly, in the mid-nineteenth century the United States undermined Mexico's long-term development by dispossessing its neighbor of its most valuable lands, imposing a border that has heavily favored U.S. interests, and paving the way for the dominant U.S. economy to compete more closely and more directly with the much weaker Mexican economy. As a result of these events, Mexicans have had to struggle to build their country under the shadow of the powerful United States, not unlike small retailers who try to survive in the face of crushing competition from a Wal-Mart megastore located uncomfortably nearby.