Freya doesn't usually fight with other dogs unless they start trying to dominate her too hard, but they said that the other dog definitely started it. She's super-friendly with other dogs and people, always wanting to play and run; she will go pretty instantly into 'kill-mode' if a dog or human attacks me, though. Freya has undergone a significant amount of fairly intense protection training, as I paid a lot of money some years ago to a guy who did a lot of Schutzhund /Mondio/French Ring/Police training with GSDs and Belgian Malinois. In addition, I used to do a lot of protection training myself with her, but the gear became increasingly expensive in light of her bad OFA x-rays eliminating my ability to breed her. So, I fixed her and cut way back on the dog training (although I still do some bite training and prey-drive drills with her on occasion).
My next dog, one day, may not be a GSD, although I really am fond of them, simply due to the difficulty of getting into an apartment with breed restrictions. The Belgian Malinois is a similar (if less attractive) breed which is excellent for protection training, and is rare enough not to appear on breed restriction lists. I'll cross that bridge when I come to it, though. Anyway I may be dropping her off next weekend if the 4-day party I'm attending takes up too much of my time.