The statement to Glenn Beck about no right to have semi-automatic weapons in cities was 2013. He's a dumbass body mechanic. He might be OK with a knife, assuming his assistants didn't do the work, but he can't think.
I admire when someone doubles down in the face of opposition, but typically one does that when one knows that one is correct.
Carson doubling down implies that he is either correct or arrogant. The former is unlikely.