Never argue with the ticked off homeowner's son while he's got an AR-15 trained on your a$$. It's a time for being apologetic and non-confrontational, not screaming at the victim that he's a racist SOB because he won't give you his stuff.
Most sane criminals upon seeing the AR15 would say “f**k this” and depart with some alacrity. You wanna argue with guy with a long gun? See ya, give my regards to lucifer.
CC