IMO the Operator was implying that if the officers arrived and saw him standing there with the shotgun, they would possibly shoot him in the “fog of war”
However a good defense attorney could use this statement to bolster the notion that the shooter was in fear for his life.
Also From the tape:
“I understand that, but I have a right to protect myself too”
He does not state, “I have the right to defend my neighbors property”
Good pick up. I still haven’t listened to the 911 call. I should probably do that so I’m a little more informed!