Courtesy of the Federalist Society, apologies for the length, but worth quoting in full to get a sense of how the American Bar Association thinks about these things:

Same-Sex Marriage Panel
The ABA held a panel on same-sex marriage Friday afternoon, titled "Marriage Redefined: Separate, Equal, or Somewhere in Between?" Panelist Rabbi Joshua Lesser-who is openly gay and active in Jewish gay/lesbian causes including Atlanta’s Rainbow Center-said that the idea that marriage has remained static is a myth. He used history to tear down the current definition of marriage to illustrate that there is no such thing as a traditional definition, stating "Women in marriage were good for two things: procreation and property. This is true in the Bible." He cited the Bible a couple of times, referencing "Jonathan and King David kissed and embraced. Now I am not saying that there’s proof that this was a gay relationship, but I am not saying that there’s proof that it was not." He then stated that Jonathan and David made a covenant with each other to protect one another’s household. Rabbi Lesser claimed that contemporary society has itself redefined marriage from what it used to be: "To say that marriage today comes from Judeo Christianity is destructive to women." He said that one man and one woman is ignorance. In speaking about defining marriage on the basis of sex, he asks, "Aren’t we better than sexuality?"
Family lawyer Sondra Harris used history as well citing the Bible, Greek, and Asian cultures where there were more than two spouses involved in a marriage. She said, "Marriage is not about love. That is a Western idea born out of Medieval times. Marriage is about property." She brought up the Council of Trent, stating that the Catholic Church didn’t treat marriage as a sacrament until this time. She then went on to cite movements in the 1970s that saw marriage as obsolete such as the Free Love movement.

The chairman of the section spoke about how Fortune 500 companies are increasingly offering benefits, stating: "The private sector has recognized the importance of this issue. Government, however, is a little slow to follow." 150 cities and 200 colleges offer some type of benefit. This needs to be done to get the best personnel and professors, she stated.

Mary Williams, of the Coca-Cola benefits division said, "What’s the big deal." She said it doesn’t really cost that much to make the change to incorporate same-sex couples.

Panelist Tom Mulroy, chairman of the ABA Family Law Section Congressional Relations Committee, compared the United States with the rest of the world and was asked what everyone else has done with this issue. His answer, "Nothing. This is a problem that the U.S. and Europe have been tackling."

Panelist Shannon Minter, of the National Center for Lesbian Rights in San Francisco, compared same sex marriage to discrimination of the past (i.e. interracial marriage, racism and people with disabilities). This discrimination is a "deep and scarring hardship for no rational reason." Attorney Kevin Clarkson of Anchorage-the same sex marriage opponent on the panel- responded, "There is no constitutional right to same-sex marriage." He claimed that the left is trying to use the Lawrence decision to redefine marriage. "You can’t claim the right to privacy argument under Due Process because there isn’t a long-understanding of a deep and firm routed history and tradition." Minter disagreed and said that Lawrence illustrates that "there’s no question that gays and lesbians have a right to claim the protection of the right to privacy." Clarkson claimed otherwise: "Nowhere in Lawrence does the Court mention same-sex marriage." When asked by the moderator what is at stake, Minter replied: Equal protection for children, family, and marriage as a tradition. "We can’t turn away from people who want to participate in marriage. What we are experiencing is a real test of constitutional and democratic principles that state we are all created equal. We will look back soon and ask ourselves, What’s all the fuss about?’" Clarkson responded: "What’s at stake is allowing the people to control public policy issues as well as the integrity of the judiciary. When the judiciary takes issues that are not in the Constitution and creates new ones, they are taking it out of the hands of the people."