There is not one
This is a discussion on Needed: 100% legal (own, transprort, use) weapon for self defense in all 50 states... within the Concealed Carry Issues & Discussions forums, part of the Defensive Carry Discussions category; There is not one...
--when I lived in San Francisco many years ago, I took to carrying a spray bottle of high ammonia content ( as strong as you can find) window cleaner in the ever-present knapsack, with the nozzle set on a narrow beam. Painting an attacker's face and nostrils with that would usually give you escape time--
--figured if I ever had to use it, I was just on the way home to clean windows as far as the cops would be concerned---I guess you could also carry it in a car--windows always need cleaning of grime, etc.,--
Didn't the Hell's Angels solve this issue by carrying ball pean hammers?
If I want a Weapon that is legal everywhere even on an Airplane. Large Belt Buckle on a heavy Belt, A pencil or Pen, keys. Think about it. You can do a lot of damage with every day things. If your not on an Airplane then there is no limit. Start with a good OC Spray.
A 1911 is Not an obsession, it's simply a recognition that it's THE Gun. :-) All others are runner ups. And hey, if all else fails, aim for the nose and fling it to knock out your foe. Let's see y'all do that with a kel-Tec. ;-)
A 1911 or an HK45. You can win them in all 50 states but not necessarily carry. No matter which state your permit is from you still will not get reciprocity in all 50 states and be able to carry a gun. But these guns are legal to own in all 50 states.
Sawed Off Louisville Slugger with some lead poured in the end.
"Life is tough but it's really tough if you are stupid"