It persistently and consistently attacked its own reflection in the passenger side mirror of one particular car (at that time we had four 80s vintage Saab 900s in the driveway). No matter where in the driveway it was parked, the bird attacked THAT car's passenger side mirror every single day, with claws and beak.
In less than a week the mirror was so scratched up it was all but unusable. I thought about shooting the bird but I found its behavior so fascinatiung, not to mention hilarious, that I let it go (the fact that I have a large stock of spare parts for 'old-style' Saab 900s on hand also entered in to my decision).
After two full weeks of daily bird attacks, I replaced the mirror glass and covered the passenger side mirror of the car with a paper bag whenever I parked it. The bird stuck around the property a while longer, but did not choose another target for its wrath. Later in the season it moved on, and has not returned.
chuckles to you and your psychotic cardinal. They are an agressive bird and chase others away from my feeders, but I didn’t know they were so selective in their enemies...:O)