I think this is the distinction. I really don’t think any amount of propaganda would get the general gen z/millennial American public to have majority support for dropping a bomb on a major city center filled with civilians.

If they drop it somewhere else in Iran and it only destroys the homeland and ruins the lives of thousands instead of millions, the mental gymnastics would be much more common. That said tho a modern tactical nuke usage against a “purely military” target would certainly open up public sentiment towards future usage.