Illegality | Illegal entry into the United States is overwhelmingly a post-1965 and Mexican phenomenon. For almost a century after the adoption of the . Constitution, no national laws restricted or prohibited immigration, and only a few states imposed modest limits. During the following 90 years, illegal immigration was minimal and easily controlled. The 1965 immigration law, the increased availability of transportation, and the intensified forces promoting Mexican emigration drastically changed this situation. Apprehensions by the . Border Patrol rose from million in the 1960s to million in the 1970s, million in the 1980s, and million in the 1990s. Estimates of the Mexicans who successfully enter illegally each year range from 105,000 (according to a binational Mexican-American commission) to 350,000 during the 1990s (according to the . Immigration and Naturalization Service).
A combination of factors contributed to sequential pronounced rises in Mexican migration to the United States during the first three decades of the twentieth century. The Reclamation Act of 1902, which expanded acreage for farming through new irrigation projects, spurred the need for more agricultural laborers. The Mexican Revolution of 1910 and the aftermath of political instability and social violence caused many to flee northward across the border for their safety, and the growth of the . economy in the 1920s attracted additional numbers of immigrants. Though the wages received by most Mexican migrants in these decades were quite low, they were considerably higher than the salaries paid for comparable work in Mexico. Most importantly, the number of jobs for foreign laborers seemed unlimited, especially during World War I and on into the early 1920s.
Ethnic Relations. Social policies aimed at the emancipation of Indian groups and the elimination of profound socioeconomic inequalities have been employed since the 1930s. Nevertheless, indigenous populations are among the poorest and most marginalized groups in Mexico. Prejudice among broad sectors of the population toward Indians persists. Elites in provincial towns in predominantly indigenous regions are often openly racist. This situation has strained ethnic relations and there has been a rise of indigenous movements in recent years that demand a new space in the national culture. Most significant has been the outbreak of armed indigenous rebellion in the state of Chiapas, where the Zapatista Army for National Liberation declared war on the government in January 1994.