What's best for children has been a central theme for a leading opponent of gay marriage.
Archbishop Salvatore Cordileone of San Francisco says marriage has always been between a man and a woman. To go against that natural order would be bad for children. The archbishop also says that gay marriage is not what nature intended.
"Only a man and a woman can unite their bodies in such a way that it can produce new life," said Cordileone.
He thinks it is just common sense that a man and a woman would provide a better environment than two mothers or two fathers. When asked if he would oppose gay couples who wanted children, Cordileone said, "I'm not saying it should be illegal for that but we should not change the definition of marriage in such a way that we enshrine in the law a principle that a child does not deserve a mother and a father."
This week the nation's leading organization of pediatricians announced their support for same sex marriage, saying there's no evidence that the sexual orientation of the parents would have an impact on the child.
"In spite of the fact that they actually face significant challenges in schools and prejudice from the world in terms of having two same sex parents, still those children are turning out you know, just equally well adjusted, equally happy, equally successful in school and in life," said Rebecca Rolfe, executive director of San Francisco's LGBT Community Center.
Cordileone disagrees, saying that if the high court legalizes gay marriage, it'll end all marriage.
"What I fear would happen is that people will just not be interested in marrying anymore. Marriage will become irrelevant," he said.
He added the church will suffer.
"If what we are teaching is bigotry and discrimination we're not going to be allowed to do that," he said.
The archbishop says the church's teachings will be identified as backwards and prejudiced and that could impact church run schools, hospitals and social service agencies.
"If we want to know how people who do hold that view will be treated, we have to think about how a racial bigot is treated in the country today," he said.
Cordileone says people are already calling him a bigot over his stance on the issue and he admits that being a visible opposition to same sex marriage is increasingly difficult. He also doesn't believe the polls that show a majority of Americans now support same sex marriage.
