Do not take advantage of foreigners who live among you in your land. Treat them like native-born Israelites, and love them as you love yourself. Remember that you were once foreigners living in the land of Egypt. I am the Lord your God. (Leviticus 19:33-34)
Today, more than 45% of the population of Mexico lives in poverty, with 10% enduring extreme poverty. Despite the fact that Mexico's unemployment rate (5.1%) is lower than the current U.S. jobless rate (6.6%), Mexican citizens still earn, on average, less than one-third of the income of U.S. citizens each year. In the U.S., workers earn an average of $50,000 per year, but south of the U.S.-Mexican border, that amount falls to $15,300. For Mexicans who cannot earn enough to support their families, sometimes the only apparent option is to travel north, legally or not.
In some ways, the United States continues to contribute to the problem. Following the implementation of the North American Free Trade Agreement (NAFTA) in the early 1990s, large American corporations took their business south, where they could pay workers a small percentage of what U.S. laborers demand for the same job. Although this migration created more jobs in Mexico, most of them pay only a pittance and offer no other benefits to workers. At the same time, industries within the United States such as agriculture and construction have come to depend upon migrant workers who will accept less pay and much harsher working conditions.
Statistics from 2014 Index of Economic Freedom (www.heritage.org/index/country/mexico); Wilson Center Mexico Institute (www.wilsoncenter.org/article/mexico%E2%80%99s-latest-poverty-stats).