In his new book, The Conscience of a Liberal, Paul Krugman cites some statling numbers regarding American attitudes toward miscegenation.  The good news is that we are changing for the better, at least viewed in the long term:

Beyond the blunt, crude fact that America is getting less white, there’s a more uplifting reason to believe that the political exploitation of race may be losing its force: As a nation we’ve become much less racist. The most dramatic evidence of diminishing racism is the way people respond to questions about a subject that once struck terror into white hearts: miscegenation. In 1978, as the ascent of movement conservatism to power was just beginning, only 36 percent of Americans polled by Gallup approved of marriages between whites and blacks, while 54 percent disapproved. As late as 1991 only a plurality of 48 percent approved. By 2002, however, 65 percent of Americans approved of interracial marriages; by June 2007, that was up to 77 percent.