“Nice selective editing:”
Nothing selective about it. Except in the small area where Arizona, Nevada, and California meet together at the pointy southern tip of Nevada, there is no Nevada wall between Arizona and California. I fail to understand your comment that Nevada is a wall between Arizona and California. Geographically impossible....Care to clarify???
It's humor. I also said that "and due to a surveyor's mistake it doesn't extend all the way down" i.e. it was misplaced/misdesigned.
The joke is that geographical impossibility.