Alan Keyes and Barack Obama both oppose marriage for gays and lesbians, but the issue produced
some of the most confrontational moments of the third and final debate of their battle for the U.S. Senate in Illinois. Obama criticized Keyes's argument that the children of gay couples, if born from artificial means and kept in the dark about their biological parents, could later end up unknowingly having sex with a relative. Calling it "a vicious attack," he claimed the argument was a subtle attempt to link homosexuality with incest.
Keyes accused Obama of denying his logic because he didn't like the conclusion. "If you can't know who your sisters and brothers are, there is no way you could avoid having sexual relations with them," the Republican former United Nations ambassador said. "I know that Senator Obama sometimes has a hard time getting from A to B."
"I think your logic was not that complicated. It was just wrong," Obama shot back moments later. Obama, a Democratic state senator, sought to show Keyes as out of step even with many conservatives by noting that he and President Bush both support civil unions for gay couples, while Keyes opposes them. But Obama struggled to explain what in his own religious beliefs leads him to oppose gay marriage. He condemned bigotry against gays and said he believes homosexuality is generally "innate" rather than a choice. But he did not offer a clear explanation of why gay couples should not then have the right to marry beyond saying that the traditional definition of marriage should be preserved. Keyes reiterated his position that gay couples should not marry because same-sex couples cannot conceive children naturally.