I drove my first car when I was 2 years old. It was a pedal-powered car my mom bought when she was visiting the soviet union. It was an excellent car, it even had suspension. I was a very responsible driver according to my parents, I never got lost and I always stayed where they could see me. Then, when I turned 16 I got my driver's license. Again, I was very responsible, I never sped, and I never drove aggressively. So there you have it, people under 18 CAN be responsible drivers. It's true that most aren't though.