In the United States, 12 states plus the District of Columbia allow gay couples to marry, and more are preparing to change their laws as well. Polls also show the social tide is shifting dramatically. In 1996, a Gallup poll showed that 27 percent of Americans supported gay marriage. In 2012, that number nearly doubled to 53 percent. So Oprah asks her panelists, the Rev. Ed Bacon, Elizabeth Lesser and Mark Nepo, 'Is this a social revolution or a cultural shift?'