It was in the middle of a scorching Californian summer, and Dallas Humber wasn't happy. She knew of an Australian who she claimed was prepared to carry out a mass casualty attack, but who didn't follow through. "It pained us all to see what happened in Australia the other day," the US woman wrote, referring to the man as a "would-be saint", in the beginning of a call to arms for her Neo-Nazi followers to unleash violence. Days before that message, Australian authorities arrested a man and charged him with a terror-related offence, among other charges. It later emerged that...