[Scenario] Would you draw on someone who brandishes their firearm?

My mom was driving to the grocery store today and had pulled into the parking lot, when a guy came storming over to her. He started yelling at her about cutting him off in traffic and then lifted his shirt to reveal a pistol, saying "You better fucking watch yourself," before walking back to his car and peeling out fo the parking lot. She was pretty shaken up and didn't say or do much while this went down, and obviously I'm pretty angry on her behalf.Now, my mom is one of the safest drivers I know and in my entire life I've never seen her cut anyone off, so I'm going to assume this guy was just a psychotic douchebag. And even if she had cut him off, it obviously doesn't justify his reaction. Not to mention, my mom is a harmless old lady in her late 60s, not someone who is intimidating in the slightest. So it seems like this guy likes to go around threatening harmless looking people, and is probably a coward who is not looking for a real fight.But it did get me thinking about how to respond in a situation like that. You have someone who is obviously aggressive, making verbal threats and brandishing their firearm. Do you wait until they start reaching for it before drawing your own weapon? Or do you beat them to the punch and possibly escalate the situation in a way that might lead to a gunfight?Curious to here some discussion and if anyone has had a similar experience, and how it played out for them. via /r/CCW https://ift.tt/2GneLdn