My post is based on a couple of situations at a prior residence while living in this state after talking to both the local sheriff and a lawyer. Every incident is different, and you are correct that that sort of trespass is highly disturbing. However, we were advised that until someone actually breaks the house the matter is not entirely clear-cut, especially to any judges or juries than might be pondering weeks, months, or years later what you had to decide in a matter of minutes, if not seconds.
That does not eliminate all potential scenarios. For example, if someone is across the street and shooting into your home you would have the right to defend yourself. Likewise, if you were standing in your yard and someone attempted to harm you you would also have the right to defend yourself.
This only applies to where I live, which may or may not apply where you live.