Reply #34: They're pretty similar when it counts

[Posteritatis]

Both of them kind of involve the person in question being in some kind of bubble separated from the person they're being a jerk to. Online you're behind a monitor, and it's still depressingly difficult to punch someone in the head through the Internet so far. In a car you're in an insulated, semi-soundproofed bubble and still kind of seperated from the rest of the world.

Both cases you've got anonymity - or at least the appearance of anonymity - and enough physical seperation from the other guy (monitor, car body, etc) for folks to think they can get away with being more aggressive.

(As I say this, I notice some asshole in the street outside my window cut off and threaten to brake-job an ambulance. WTF, people?)