Protection > Property Property
This may surprise you, but your house is not bulletproof. Whether you have bricks, cinder blocks or concrete, a bullet even from a handgun could potentially pass through and kill someone. (depending on the gun caliber).
So, the question becomes, how do your fortify your house against bullets (stray or intentionally fired at you), without looking like the crazy neighbor.
Survive a home invasion
https://www.youtube.com/watch?v=L84WvNsdU_M