coy threats like that are actionable only under FCC rules for interstate telephone usage if you called a person across state lines and the person you called feels that they might be in the subclass of targets. But posting in a open forum not intended for a specific target to see is ruled non-actionable as a "personal threat". FCC phone usage was a wiggle room chipping away of free speech but some argue it was needed because of implied mafioso threat tactics to coerce parties