With 3D printers, getting a gun could be as easy as downloading it. A person can find a schematic for a firearm online, plug it into a 3D printer with the right materials, and that’s it — a gun is created on the spot. No background check required, no serial number to trace the gun if it’s used in a crime. The fact that anyone with access to a 3D printer could potentially create a gun is alarming — especially as gun violence is already so high in the U.S. with mass shootings happening at least once a month.