Utterly false. Morality is legislated every day. What IS the law but enforced morality? What are the laws about theft and robbery, but a codification of "Thou shall not steal"? What about legislation about "hate crimes", discouraging smoking in public, etc, etc?
The proper venue for legislation is to discourage actions which would tend to be harmful to society. Single motherhood is one of THE MOST DESTRUCTIVE activities to a modern society.
My original comment was related to thinking anyone in this country would be ok with someone saying you cannot have a child if you are single and therefore, the only way to ensure you don't have a child if you are single means no sex if you are single. THAT kind of morality cannot be legislated.
The Puritans on this site can think it is possible to achieve their vision of how people will live their life, but it will never happen.