I've never read the air bag part of the motor vehicle law, but I don't believe that they are required, but what is required is something that protects the driver without them playing an active roll in it, but as I understand it Air Bags are required because auto makers are required to install automatic restraint systems, first idea along this line was automatic seat belts but the lap belt part still had to be pulled across and latched so it was a net loss due to lack of use of the lap belt, ideally we would all have 5 point harnesses but that is not going to happen, so what would I like to see instead?