Officials believe Hasson, who self-identified as a white nationalist, was taking notes from a manifesto written by Norwegian citizen Behring Breivik, who killed 77 citizens in two coordinated terror attacks in July 2011. Breivik spent three years writing a manifesto on “Crusader Nationalism,” in which he warned of a wave of Muslim immigration brought on by “Cultural Marxism and political correctness,” according to the court documents.