Why are old farts allowed to drive in the US, when they have such an overblown sense of fear? The LAST person you want behind the wheel of an automobile is somebody who is afraid of driving!!!
In many areas of the U.S., there is no public transportation to speak of, and NO BUS SERVICE to school at the high school level. Unless you advocate many kids drop out of high school, there is a need for many of them to drive to get there. Walking many miles both directions is not practical, and the parents who are both working can't afford to quit their jobs to taxi the kids around. Besides which, many U.S. teenagers need to start working YEARS before they are considered to be adults, and need motorized transportation to get to work and back. Again, they can't count on the parents to taxi them around, so they have to drive themselves, or get a ride with a sibling.
FWIW, I grew up in an area of the U.S. where I had my first unrestricted operator's license at the age of 14. Some of my peers at the time were MUCH better drivers (at the age of 14-15) than my wife is now. And my MIL's driving scares the HELL out of me.
Teenagers can be very good drivers. The problem is that teenagers are inexperienced. As such, they tend to have a lot of unintentional collisions. But raising the minimum driving age would MOVE those collisions, not prevent them. That is, if the minimum age for driving was 21 for example, then a lot of inexperienced drivers in their mid-twenties would have the collisions that the teenagers are having now. -Dave