Defending the turf

As I stood on our roof this afternoon with an inspector from the roofing company, I noticed the dog from across the street escaped from his yard with his de-anchored chain in-tow and wandered into our front yard where I chained Dillon.  The roofer warned me to make my way down the ladder and attend to my pup since the intruding dog is a pit-bull.  With a minor hesitation, I calmly yelled out to our neighbor to come and retrieve their pet, but it was more for their mutt's protection than mine.  Dillon, though disadvantaged with a chain and smaller stature, defended his turf without an ounce of fear as the intruder circled around in a weak attempt to assess the situation.  The dog's owner took him home and Dillon stood his ground.  Pit Bull?? He might as well have been Red Bull.