Writing disturbing fiction is illegal in some states. "Disturbing" is left up to interpretation by judges and officials, but say, for instance, you live in Kentucky and you write about a fictional military attack? That could be seen as a terrorist threat and a felony. In other states, writing about someone getting hurt can be considered a threat or plan to cause grievous bodily harm. Oh, and this isn't published work or works posted online. If they find your journal and you write, "I hate Person X at school, I wish she'd get pushed down the stairs and break her leg!" and it's found, you're in big trouble. Sweeping laws that can be easily taken out of context are bad, okay?