Chapter 8. The Costs of Homeland Security

The US-Mexico border has undergone several historical transformations. Between 1848 and 1920 the border went through an era best characterized by informality: there were no border guards, no customs controls, and no checkpoints. This era is best referred to as a frontier system. In general, although a line divided the two countries on the sand and the river banks, border controls were practically non-existent. The Mexican Revolution of 1910-21 brought a new era for the border, one better refe..