Also: Have you looked up the Permissive Action System and the Soviet/British equivalents? Nuke security is oldschool, and literally bombproof. It’s like the old magic of our world. Of all the concerns I have around nuclear weapons, their security failing is the least of them. The one exception is North Korea, and anyone else “new” who gets them like Iran. They won’t necessarily adhere to the costly standards the Cold War powers did, so there is more risk of lost control.