Assault weapons due noting to help you protect yourself, your home, or your family. They do help people who want to hurt/kill as many people as possible in as short a time as possible. You're not reaching for your M4/Ak47 if you hear a noise at night, but if your goal was to walk into a mall and drop as many people as you could before the cops get there they are a great selection. Therefore a ban wouldn't restrict law abiding citizens but it could at least help restrict mass shooters.