[Coda]

Unless you get a license, it's illegal to carry a gun in Tennessee, too; that's not an exception. The general concept behind the law is that you shouldn't be toting around weapons in public places without a license, and there's no licensing scheme for weird weapons.

Really, the ideal self-defense weapon in Tennessee is a large folding knife. Tennessee repealed its knife restrictions a few years ago, so a knife that you would very reasonably carry as a tool is absolutely legal to carry, regardless of length or opening mechanism. They raised the criminal penalties for using a knife in the commission of a crime, so they're still trying to deter the use of knives as weapons, but they're not going stupid about it like London.