ballistic missiles or not, you would have to ERASE the country and its population out of existence COMPLETELY because you can’t possibly send off every man woman and child to siberia or “convert” everyone if they are holding firearms.

you simply cannot have armed people willingly load themselves into railroad boxcars

you would at least had a fighting chance with 3D printed guns and could have deterred any threat, foreign or domestic without involving corrupt government and bloated centralized spending