I'm a huge pro-2A supporter, but even I'm having a hard time agreeing with you on this one. If someone is in FRONT of you, and you've avoided a rear end collision with them, the very next thing you should do is slow down and let them go, not grab a pistol and keep following. I can't even imagine a situation where a gun would even come into play unless you actively go after him, or both of you decide to stop.

A firearm should be your last choice after you've exhausted all other options, not the first thing you grab when someone pisses you off.