While I understand how quickly a situation can become violent, and believe in being prepared to end a threat, drawing a firearm in anticipation of a threat that has not been made is generally against the law.If you can, watch the home break-in/beating of the middle age woman in New Jersey.
She's in her living room watching TV then a big thug bursts in & starts to pummel her.
These attacks may seem far fetched but I doubt the home owner/mom was prepared.