In actuality, Horses are not all-out agressive, although they have a strong sense of warrior tradition, leftovers from their past as soldiers for ancient Equestria. They prefer to be left alone, but trade ocassionaly with Earth Ponies (and any other equine race - except Pegasi and Unicorns) for what they lack.
Diplomacy is much preferred, but if you back them into a corner? It's so on, it cannot be turned off. Hope you like being kicked, trampled and tossed aside by a ton of enraged animal. A ton of Horse smashing into you at 40 miles an hour is going to leave a mark...
No, they would never think of fighting with Equestria. Equestria has two Alicorns on the throne, and Horses stil retain a deep sense of ingrained reverence and respect for them, even though they've been isolated (by choice? by force? I havent decided) from much of Equestria for over a thousand years.
I'm going to have them prostrate themselves to
Twlight, as she has a horn, one of the Symbols of Royalty. Then they get confused when they don't see any wings. Or something. That scene is frustrating me right now.
edited 13th Dec '11 12:35:11 PM by pvtnum11