Why New Zealand mosque suspect represents 'social movement'

Deadly terror attacks in New Zealand Friday caused global shock, but the extreme anti-immigrant, white supremacist ideology of the suspected Australian gunman is not new. Judy Woodruff talks to Humera Khan of Muflehun, a nonprofit fighting hate and extremism, University of Chicago’s Kathleen Belew and Matthew Knott of the Sydney Morning Herald about the scope of this malignant "social movement."