I think a good example would be the Civil Rights Movement. It took charismatic speakers such as Martin Luther King to build an audience. Once enough people listened, how things were done in the past were reevaluated. New laws were then written. Society changed.
Traditional families have also changed. No longer is every family on the block arranged with a mom and dad and brothers and sisters. Easier divorce laws have made step families a type of norm. Or in many cases, some parents do not even get married which is now acceptable but wasn't in earlier times.
This is why I think rational authority has overtaken traditional authority. New laws make it possible to look a head and not always do what has already been done.
This is a picture from the show Modern Family which shows that families are made up very differently than in the 1950's.
http://t0.gstatic.com/images?q=tbn:ANd9GcQ2UiI17jib6lk6kz9XmMNSbAsRSx1M-EuwYgtRO99EzUBbCHeu8w