What needs to happen is the abolition of NAFTA.
Free trade has devastated the impoverished Mexican poor and actually caused a higher rate of migration. Maquilaora factories pay dirt cheap wages and the land that belonged to local peasantry has been sold to American corporations. Now without traditional homeland and with only the worst wages available to them, they are pushing into the United States with greater frequency. And that is partly our own fault for exploiting them.