I wonder if someday there will be a Heller like challenge to the insane knife laws in the United States. In some counties, it is a felony to carry a knife with a blade that exceeds 1.5 inches. Whole classes of knives are banned in many states, supposedly for their weapon like qualities. A knife is a tool, but if the state wishes to define it as a weapon, then the 2nd amendment should apply - after all, arms always meant more than just guns, it meant weapons.