'As a mayor, I know that legalising same-sex marriage has sharpened New York City’s competitive edge, because it has made us an even more attractive place to live and work.' Across Europe and the US support for same-sex marriage is growing, and for a simple reason: it is consistent with democracy's promise of equal rights for all people. As long as government is in the business of handing out marriage licences, all couples – regardless of their sexual orientation – deserve equal status in the eyes of the law. I believe that it is only a question of when –...