In a survey of 120 major cities New York was found to be the ninth most unequal in the world and Atlanta, New Orleans, Washington, and Miami had similar inequality levels to those of Nairobi, Kenya and Abidjan, Ivory Coast. Many were above an internationally recognised acceptable 'alert' line used to warn governments.
"In western New York state nearly 40% of the black, Hispanic and mixed-race households earned less than $15,000 compared with 15% of white households. The life expectancy of African-Americans in the US is about the same as that of people living in China and some states of India, despite the fact that the US is far richer than the other two countries," it said.
Obnoxiously, the article provides no information that you can use to actually find and read the report they're summarising. (It's from a `new United Nations report on the urban environment'. Thanks, John Vidal!)