Dog is violent towards doors and other dogs

We have two Pompoos. They are a year apart. One is 7 the other is 6. The 6 year old is the more dominate. He likes to show that towards the other dog. Out of no where he will attack the older one. He also will attack any door that is being closed. He has almost destroyed our bedroom door. We love him. He can be the most sweet and loving dog that you could ever want. I am sure he is jealous of the older one. He wants to show him that he is the Alpha. But the door issue I can not figure out. Any help would be great!