Bullies are not born, they are made. They learn from an early age that its OK to push smaller or more timid kids to get their way or hurt others.
I think we should consider mandating classes in courtesy, manners and respect at the earliest ages possible. Two to three years old is not too young to help prepare children for a future life in a civil society.
Along with what a person likes to eat, a childs attitude toward life is already engaged by the age of 5.