So apparently, Barack Obama is finally done evolving.That, you will recall, was the president's word for the process of reconsidering his opposition to same-sex marriage. Last week, after being publicly and inadvertently (?) prodded by his vice president, Obama announced the results of all that cogitation. He told ABC News he has "just concluded that for me personally it is important for me to go ahead and affirm that I think same-sex couples should be able to get married."It was a historic statement from a historic president, a moment of political courage from an administration that has provided fewer such moments than you would like.