They didn't need to know how complex our society is now. The founding fathers knew that without trusting the people's responsibility, our country would never work. No law can discipline a young child as well as a parent. It's like trying to put laws in the parent's positions. A good parent would never let his child take a gun to school in the first place.
Children are their parents' responsibility.
If all parents would raise their children to be responsible citizens, they would grow and raise their children to be responsible citizens also. Our society would face fewer problems. Children need to know the consequences for all actions, and that there are punishments for things done wrong. In recent years the United States government has allowed itself to become the parent of the American people by taking on all of the responsibility which should rest on the individuals. Congress continues to pass laws that from the beginning are viewed as meaningless.