While driving in Beijing with a friend we discussed this use of horns – especially on highways. He comes from Beijing but currently lives and drives in the US so has experience with both approaches. His comment was that the US driving culture is based on the driver providing notice of his intended actions to cars behind. The Chinese driver provides notice to the cars in front.

The former allows for the use of visual clues – such as turn signals – because drivers behind him can see the indicator in front of them and act accordingly. The latter requires a sound clue – a horn being the only one available except for shouting – because drivers in front can’t risk taking their eyes off the hectic traffic on front of them even for the seconds it would take to look for rearward visual clues in rear/side view mirrors or – god forbid – looking over their shoulder.