Interesting parallels to drug prohibition -- also largely promoted (initially) on overtly racist grounds (keeping blacks/mexicans/chinamen with their evil cocaine/marijuana/heroin away from white women/children). Then, additional justifications from public health or public safety grounds, which largely stand on their own as arguments today. (I'm willing to accept that many guns and many drugs might have worse consequences than if they were never invented) And leaky prohibition today, where the majority of problems are caused by the illegal drugs or illegal guns, but some problems caused by legal guns and legal drugs too.
Maybe it's just that each is a powerful technology.
Maybe the next powerful technologies will be 3d printers, drones, desktop chemical synthesis, cryptography, and the Internet.