The anger is cultural. For some examples, look a sporting team logos - from school-age teams all the way to professional. Half look like they are about to bite

The anger is cultural. For some examples, look a sporting team logos - from school-age teams all the way to professional. Half look like they are about to bite your head off and the rest look constipated. I think a significant part of road rage is due to conflicting metaphors. Children are taught to "wait in line" and "take your turn". The lanes on roadways emphasize the "wait in line" - but there is no line. So when people pull in front of you, they're violating a deep-seated upset-ness that they are cutting in front of you. But there is no line - so it is impossible for them to "get to the back of the line". I could write a very long essay on these conflicting metaphors and how our tricksy monkey-brain and lizard-brain are perceiving and sending conflicting messages. Additionally, the semi-anonymous nature of driving has the same lack of feedback that posting on the internet gives. You will say and do things that you would never say/do to another human in front of you. Add to that an appalling lack of driver education/training in the US and the question should rather be "why is there so little road rage?" Finally, the public policy has been to make things so spread out that car ownership is mandatory. Zoning requires f(X) number of parking places if your business location can handle X number of customers. This is why all businesses (both retail and office) look like a box in the middle of a parking lot.