OWOSSO, Mich. – Officials outlined how they say a Michigan man plotted a mass murder at two nearby locations. Mack Davis, 23, of Owosso, “became infatuated with other mass murderers and planned to conduct his own,” court documents say. He drafted a list of weapons and tactical gear for his plan, and his writings show that he surveilled churches, synagogues, mosques, schools, hospitals, and supermarkets, according to federal authorities. Davis wrote about his “hate for this world and for the people in it, all people,” saying, “I hate you all the same,” officials said. He posted pictures of himself making...