See herein lies the problem. It was always viewed that if you put up bars on windows or big steel screens you have something of value you are trying to protect. Like adding a safe. IMHO in this day and age, CCTV's and motion activated lights are a far better deterrent against people trying to break and enter to hurt you or steal. My wife used to be a bit concerned of "Intruders" early on but with the add of CCTV she never even thinks about it and of course our 4 dogs create a stir with anything entering the yard. I also believe being our living area is on the 2nd floor, it would make a break in quite a challenge.
Knock on wood, our place is in an older mooban and everybody knows everybody and if someone broke in and took something from someone I guarantee that our Grand Poobah leader would be on the PA system making an announcement about it.