As an estimated seventy-five hundred migrants continue to head north through Mexico, CNN Correspondent Bill Weir joins Christiane Amanpour from Huixtla, Mexico to discuss the latest on the ground. Jorge Castaneda, the former Mexican Foreign Minister discusses Trump's backlash against the migrants. General Stanley McChrystal, the former Commander of U.S. Forces in Afghanistan discusses leadership and his new book "Leaders: Myth and Reality." Our Walter Isaacson talks to Theoretical Physicist Brian Greene about how quantum computing could alter our future. via Knit