A national urban policy would not have saved Detroit, but the city's bankruptcy filing Thursday was a vivid reminder of how the problems of America's cities have long ceased to be a focal point of the political debate in presidential campaigns or on Capitol Hill.

The closest the candidates came in 2012 to the topic was the contentious argument between President Barack Obama and his Republican challenger, Mitt Romney, over the federal bailout of the auto industry.

Obama pummeled Romney over an article he had written for The New York Times in late 2008 opposing federal intervention. The headline, which Romney did not write, read: "Let Detroit go Bankrupt."