If you feel threatened, in my opinion there is nothing unethical or immoral about defending yourself. I have had problems in the past, mostly with dogs people take out and dump in the country that find their way to my house. Most of them are glad to see a friendly face, but a few are problems. The ones that are problems have to be dealt with, and this looks like the situation you are in. In only a few cases was the problem a neighbors dog. When it was a neighbors dog, I contacted the neighbor. Most took appropriate themselves.

If the dog is blind in one eye, his difficulty seeing may be part of his outward aggressiveness. Many times, when a dog is acting agressive, it is more out of fear than anything. I have never been bitten by a dog, although there have been several close calls. I find turning and facing them to work well. If they know your not afraid of them, they will be a little more respectful of you.