Why are immigrants willing to risk their lives and take their families across the border?

In 2006, Mexico’s newly elected president, Felipe Calderón, declared war on his country’s drug cartels. He militarized and intensified a conflict that had been managed by his predecessors through an opaque strategy of accommodation, payoffs, assigned trafficking routes, and periodic takedowns of uncoöperative capos.

The “war” is going poorly. Mexico’s murder rate, which had fallen by fifty percent between 1992 and Calderón’s inauguration, has about tripled since then. A murky, multi-sided conflict has descended into one involving severed heads displayed on pikes, mass executions, disappearances, attacks on journalists, and urban shootouts among the cartels’ trained paramilitaries. About forty-five thousand Mexicans have died since Calderón called out the dogs. Many thousands of the victims are public servants—police, judges, mayors, and legislators—or civilians caught in crossfire. In the name of defending them, the country’s military has carried out horrifying atrocities, degrading the legitimacy of a state that was weak enough to begin with, as a Human Rights Watch report released this week documents.