The following is a rather lengthy excerpt from Frank Turek's book Correct, Not Politically Correct: How Same-Sex Marriage Hurts Everyone:
"Homosexual activists claim, without any evidence, that parents are interchangeable - that two men or two women can do just as good a job parenting as a man and a woman because men and women offer nothing unique to children.
This raises the following question for those making such an absurd and unsupported assertion: Why do you think that men and women are interchangeable as parents but not as sex partners? I mean, if men and women are really interchangeable, then why not just marry someone of the opposite sex?
Think about the inconsistency here. When it comes to their own personal gratification, homosexual activists clearly recognize the big difference between the sexes. Only when it comes to the more important priority of raising children do homosexual activists say there is no difference between the sexes. Children are just going to have to take a backseat to homosexual sexual desires. Dr. Jennifer Roback Morse sums up the attitude of homosexual activists well. She writes, '[Homosexual] adults are entitled to have what they want. Children have to take what we give them.'
People who deny what's best for kids in order to have the sex they want show that they do not have the best interests of children in mind. This is another reason why homosexual relationships should never be equated to marriage. Marriage means much more than just sexual coupling as all children know."