I bet the Australians never thought to see an outright ban.
Or the descendents of the people who wrote and fought for the Magna Charta.
Under enough pressure the supreme court would rule for almost any kind of stupidity. Look at the New Deal and what went into engineering that. Look at the thread on the interment of Japanese Americans during WWII, before the Nazis gave them a bad name the actually called them Concentration Camps. Which is what they were in the same sense of the term as used by the Spanish and British in prior decades.
If it happens it will be incremental. Ban self defense for citizens and thus no legitimate reason for handguns, etc.
Decent law abiding people must fear criminals and the law while criminals have nothing to fear.