You don’t always have to kill something to remain safe. Driving an intruder or dangerous animal away lets them know your territory is off limits. A wild animal will less likely return if there is an uncomfortable response to his being there. A stray dog will move on the next easier target. Humans will also retreat if faced with a powerful pepper spray or stun gun. Lights, loud noises and measured physical response will go a long way in turning a threat away from your property.