I just want to throw my $.02 in... why? Because I can
First of all, there have been a lot of 'absolutes' in the opinions expressed here. Unfortunately, there really aren't any absolutes when it comes to dealing with firearms and our justice system. Otherwise, some people would be in prison right now, and some would have never gone. I can't say ABSOLUTELY whether I would shoot someone for stealing my car. I don't have the insurance because I can't afford it because too many people WOULDN'T shoot people for stealing THEIR cars. My family currently has only one vehicle, and if you steal that, you steal my livelihood.
Now... on to "brandishing". Again, there have been many 'absolutes', but there is no absolutes in dealing with self defense, etc. Let's first dispense with some definitions and conceptions. Brandishing
a firearm means pulling it out and waving it around. It's a stupid thing to do. Presenting
a firearm means drawing it out from concealment and assuming a defensive posture... from being at low ready to taking aim. Presenting a firearm constitutes the use of deadly force. Can you present your firearm? Sure... as long as you are already authorized/justified in using deadly force. Does it mean you HAVE to shoot? No.
It's quite difficult to justify displaying a firearm while in a moving vehicle. If you're in a vehicle that's moving, you are already set up with an escape mechanism. You can't really "present" a firearm while in a moving vehicle if you're the driver, so it's best to just keep it handy and slow down enough to make evasive maneuvers or minimize injury should the attackers become aggressive enough to bump into you, but go fast enough to avoid looking like you want to stop for a real confrontation. Defensive driving is all about you, not them.
I'm sure that last paragraph doesn't sound like I want it to... maybe I should stop posting at 2am???