Following the 1917 revolution, the ruling Institutional Revolutionary Party (PRI as a Spanish acronym) spent several decades attempting to implement communism but ultimately devolved into almost pure corruption. The election of Vincente Fox Quesada in 2000 removed the corrupt semi-communists from power. Mexico actually ranks among the richer nations of the world; however, several states, especially Chiapas and Oaxaca, continue to suffer from communism. Crime and corruption run rampant throughout Mexico, especially in Mexico City and the norther border regions. Mexico's northern neighbor is far more prosperous and powerful, so many oppressed, impoverished, criminal, or opportunity-seeking Mexicans cross the border.
"Mexico actually ranks among the richer nations of the world"
Because It's large.