I've lived in Michigan, Indiana, Texas and now California. At one point I had an industrial sales job and covered 5 states by car - usually putting around 60,000 miles on the company cars I had back then. I've driven a hell of a lot over the years and seen all kinds of drivers.

People in California are generally totally oblivious to the world around them. Their cars are like little cocoons that envelope them and seal them off from the rest of the world. Tailgating is rampant out here - it is common to see a full size SUV riding less than 20 feet of the back bumper of a small car, sports car, Euro sedan (any of which will easily out brake the SUV) while cruising along at 70+mph. At times it downright scary, even when I'm NOT the one being tailgated. Just seeing this stuff go on around me gives me pause at times.

I don't think any aggressive driving is necessarily aimed at a particular make or model of vehicle, I just think that most people don't pay attentiion, are oblivious to the world around them, don't really know how to handle a car, don't understand the concept of "etiquette", and don't look any further ahead than the bumper of the car in front of them.