Kirstjen Nielsen says she left DHS because 'saying no' wasn't enough

Former Homeland Security Secretary Kirstjen Nielsen said she left office because "saying no" and refusing to do things that others in the administration wanted was "not going to be enough." Her comments came towards the end of an intense and brief interview with Amna Nawaz, national correspondent for "PBS NewsHour," which focused primarily on Nielsen's controversial role in the separation of families at the border.