It sounds like a temperament problem more than a training or medical problem, as the dog has been this way from the beginning. Your description sounds like he is a sharp-shy dog who is reactive out of fear and insecurity. The constant destructiveness supports that he is a very anxious dog. "The sharp-shy dog is the epitome of bad temperament. He is easily driven to panic by the unfamiliar... This psychologically unstable animal will, if the occasion arises, bite one of its owners in blind panic without even being aware of having done so." Often this type of dog is put down/euthanized.
Last edited by Chip Blasiole; 05-20-2019 at 12:00 PM.