It's not a simple issue of one hit for one hit. Generally, the law expects you to try to safely remove yourself from the situation before employing "self defense". If someone hits you and you have the ability to flee, you should, and call the police. If you are cornered and do not have the ability to flee without subjecting yourself to multiple strikes, you may use an appropriate amount of force in self-defense in an effort to remove yourself from the situation. In short, it is best to try and avoid the confrontation all together. If your neighbor has threatened to attack you, you should notify the police of the threat so that if there is at some point a physical altercation, your claim of self-defense will be more credible having documented the threat from your neighbor.
LEGAL DISCLAIMER Mr. Rosen practices matrimonial and family law in Great Neck, NY. His response here is not legal advice and does not create an attorney/client relationship. The response is in the form of legal education and is intended to provide general information about the matter in question. Many times the questioner may leave out details which would make the reply unsuitable. You are strongly advised to confer with an attorney in your own state to acquire more information suited to your particular circumstances.