I support ignoring your bully, telling authority, getting advice from wise adults, sabotaging their juice box with glue, if all else fails restraining orders are nice. If someone is backed into a corner, they should definitely defend themselves...but there are sooooooo many peaceful solutions out there one could do before they decide to blow their brains out.
Not everyone who's "backed into a corner" is of sound-mind to decide the most rational way forward.