Legislating Morality

Dear readers,
For years I have believed it impossible to legislate morality. In fact, I included that line in the book. But after thoughtful consideration to our history of legislating immorality - that is, relaxing or changing censorship, prohibition, abortion, or other laws designed to assist us in reigning-in the worst of our nature - it seems as though the opposite must be true.
So, what is the answer? Do we lock Pandora's Box, or leave it wide open and suggest that nobody "go there?" If there is a viable middle ground, what would it be?
Sincerely,
RMW